My 9 Biggest Investing Mistakes – How to Avoid Them!

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9 biggest investing mistakes

Everybody will do some mistakes in his life. There is no way around it. Over the years, I made many investing mistakes. One thing is very important with mistakes is that you learn from them. Not only should you not repeat your mistakes, but you should also improve your knowledge after you have made this mistake. You need to understand why this was a mistake and how to not do it again.

It is very important to learn from your mistakes. And it is also very important to recognize your mistakes. There is no value in thinking you cannot make mistakes. And there is no value in ignoring them. I am not very proud of my investing mistakes. But it is better to talk about them than ignore them! And people can learn a lot from the mistakes of other people.

In this post, I will talk about my 9 biggest investing mistakes and what I could have done better. It is also the story of how I got into investing early and left very early. And finally started investing again way too late!

1. Not holding funds

My first attempt at investing was around 2014 when I was 25 years old. I was contacted by my bank at the time (Raiffeisen). I was offered a large choice of funds. At that point, I had zero experience with investing. I did not really know what to do. I decided to invest about 4500 CHF in their funds.

For this, I chose three funds, one bond fund, and two stock funds. I chose mainly based on past performance. Actually, I was smart enough to choose funds with some diversification and with some interesting stocks. But I had no idea what the Total Expense Ratio (TER) was. One of the funds had a 3% load fee and 1.25% TER. This is a really bad fund. I should have made more research.

The first of my investing mistakes was to get out too quickly. At first, the funds did pretty well, but then the USD dropped a lot and canceled my earnings. After some time, I decided to sell. With a very small profit. I tried to cut my losses early. Had I waited a few years, I would have made a very good result. I sold based on emotional reasons. I should have held my investments. One should always hold investments and never make an investment decision based on emotions.

2. Not investing early enough

This one is probably the biggest of my investing mistakes. After my first attempt at investing, I waited a long time for investing again. In late 2015, I opened a funds account at PostFinance. I do not remember exactly what made me invest at that time. I think it was suggested by my bank advisor. This means I was out of the market for almost two years.

So, I started investing in PostFinance Fonds 3. Again, I chose without enough research. I chose this one because it was suggested based on my investor profile at that time. This fund has a 0.5% load fee and 1.11% TER. This is of course way too expensive even if PostFinance advertises it as cheap. It is relatively well diversified but is not an index. And it had a too large allocation to bonds for me (65%).

Nevertheless, it is still better than being out of the market. I should have invested again earlier instead of waiting for so long. Ideally, I should even have invested before my first attempt at 25. But nobody ever suggested it to me before that time. And except for some movies and books, I had no idea what was the stock market.

3. Ignoring the fees of funds

At some point, I started to learn that the cost of my PostFinance fund was too high. There were so much better options. First, I decided to simply use other funds offered by PostFinance. They have a few funds with TER below 1% and several funds are no-load. So I started investing in these funds. I made a portfolio of 6 funds. If I remember correctly I had a global fund, a United States fund, an emerging markets fund, one dividend fund, a bond fund, and a technology fund. This is not a really bad portfolio. However, It was a bit complicated. Later, I learned to simplify my portfolio.

The average TER of my portfolio was better now. But it was still way too high. It took me a few more months to learn about really cheap funds and Exchange Traded Funds (ETFs). At first, I researched if I could do on PostFinance but their fees are absolutely outrageous. I recommend that trading on PostFinance be avoided at all costs ( ;) ). After researching several options, I decided to use DEGIRO as my broker. Then, I started investing in the Vanguard Total World (VT) ETF. From this point, I invested in low-cost funds only. With a cheap broker and cheap ETFs, this made my overall fees very low.

This mistake taught me that fees are very important. They can make a large difference in the long-term.

4. Investing in cryptocurrencies

Another of my investing mistakes was following the crowd and buy into crypto-currencies. I started to buy some Litecoin (LTC) on Coinbase. Then, I invested into Bitcoin (BTC) and Ethereum (ETH) through an Exchange Traded Note (ETN). I was just following the crowd and thinking it was dumb to miss the returns. And of course, I invested way too late. I bought just 5 days before the all-time high. Fortunately, I did not invest a lot. I put around 700 EUR in Bitcoin and around 220 EUR in Ethereum.

And then, it crashed. The price went from a high of about 19K USD to a low of less than 7K. It lost more than half of its value in less than two months. I did not sell at a loss at least. But I decided to go out of the crypto-currency gambling game. I do not think BTC has any real value, only a gambling value.  It is not a smart investment. Moreover, there is too much volatility for my liking. I was already able to sell my Ethereum for about 30 EUR profit. But I am still holding on my BTC ETN. I am still down 45% on this investment. I am not sure I will ever be able to sell this fund for a profit. But I will at least wait until the end of the year before selling at loss.

This taught me not to gamble my money. Smart investing is not gambling. And cryptocurrencies are a gamble.

5. Investing in a too complicated portfolio

Once I realized that index investing with low-cost funds was the way, I set up on design my portfolio. I tried to be smarter than other people. As a result, I ended up with a portfolio that was too complicated. I had too many funds. Several funds were not as useful as I thought. And I even chose a fund that was not what I wanted. You can read mistake #8 to find out what it was.

There are many examples of simple portfolios in personal finance blogs. Most of them are using a three-fund portfolio or even a two-fund portfolio. It is not necessarily easy to adapt for non-US investors, but it is doable. My new portfolio only has three funds. And it could be simplified further to two funds. A simple portfolio is easier to manage and to rebalance. And it is often more efficient than a “seemingly smart” one. People are not beating the market on the long-term. Therefore, there is no point trying!

6. Investing first, asking for advice second

This investing mistake is directly related to the previous one. When I decided to invest in my complicated portfolio, I did not check with anybody. After I did the investment, I asked for comments on the portfolio. And most of the comments agreed that it was too complicated. If I had asked for advice before investing, I would have avoided investing in my complicated portfolio at all.

I think it is always a good idea to ask for advice before investing. You can ask advice on your favorite personal finance blog or on the bogleheads forum. Ideally, you want several points of views on a decision before making it.

You should always ask for advice if you are not sure about something. I am running a finance blog and yet I still often ask for advice from people that are more knowledgeable than me. Moreover, this can also break a bias that you have in your decisions.

7. Not considering the big picture

In 2018, I decided to add 5% bonds to my investing portfolio.  My rationale was to help to rebalance my portfolio and to increase my bond allocation. However, I did not consider the big picture. I only considered the bond allocation of my investment portfolio. But I have also bonds in my retirement portfolios. Once I took everything into account, I realized I already had a too large allocation to bonds.

You should always consider the entire net worth when taking an allocation decision. Once I had the big picture, I saw I needed more stocks. I ended selling these two bond funds when reviewing my portfolio. Fortunately, I realized this early enough. However, it made me waste time that I could have spent doing better things.

8. Buying without enough research

This one is a bit silly of me. I bought Vanguard FTSE Pacific ETF and allocated 5% to it in my portfolio. My goal was to add more Chinese exposure. However, this ETF only covers developed Asia and for some historical reasons, China is still part of the Emerging Markets, not Developed Markets. Therefore I bought the ETF for Chinese exposure, but there is none in this ETF. I did not research enough. There is nothing wrong with this ETF, it just was not what I wanted. I ended up selling this fund.

While you should not make a complicated, you should still know what you are investing in. There are many options for stock market indexes. And for each of these indexes, there are also many options of funds that are tracking them. Therefore, it is very important to research these options!

9. Not considering professional bias

I work in the tech industry. And I am a big geek, I really like technology. So I decided to invest a small part of my portfolio in an Information Technology ETF. I did not consider that Tech was already present in my other investments. In my global world ETF, there is about 15% of Technology and 6 of the top 10 holdings are technology or internet company. This is already a large bias in Technology.

But my real mistake here is that I did not consider that my job is also a bias towards Technology. Currently, my job is not linked to the performance of the tech industry, but my next job will be. If the Tech Industry crashes, both my job and my stocks could be at risk. This is not a really good idea. Too strong bias to the sector of the job should be avoided.


As you can see, I did my fair share of investing mistakes over the years. I wish I had realized this before. However, I am only 30 years old, so there is still some time to apply a better strategy now. I am sure I will still do several mistakes in the next years. And I will let you know about them on this blog of course. But I am now smarter than before and I will avoid repeating the mistakes of the past at least.

The most important thing with investing mistakes is this. Do not repeat your mistakes. Learn from your mistakes. Doing a mistake is not always a big deal. But doing it a second time is a big deal. If you learn from your mistakes, they will transform into powerful teachings.

If you liked reading about my investing mistakes, you will like reading about my budgeting mistakes.

What about you? What were your biggest investing mistakes?

About the author

Mr. The Poor Swiss

Mr. The Poor Swiss is the main author behind In 2017, he realized that he was spending more and more every year, falling into the trap of lifestyle inflation. He decided to cut on his expenses and increase his income. This blog is relating his story and findings. In 2018, he saved more than 40% of his income. He made it a goal to reach Financial Independence. You can send Mr. The Poor Swiss a message here.

18 thoughts on “My 9 Biggest Investing Mistakes – How to Avoid Them!”

  1. Hahah. Some mistakes are extactly what I had make. And it’s it’s a very good advice for the investment starters.

    1. no matter the amount of advise, IMHO everyone needs to make their own mistakes.

      I did a few myself and learned from these:
      – crypto= gambling
      – timing the market= not possible
      – fees matter (a lot)

      1. Hi Zoli,

        You are absolutely right. Everybody will do mistakes. It is important to learn from them and not reproduce them.
        You’ve got some powerful lessons from your mistake!
        I know that a lot of people will still do the same errors as I. However, some of them will not be done and as such, I believe it has a purpose.

        Thanks for stopping by :)

  2. Sometimes the way we learn best is by making our own mistakes. The important thing is to learn from them and not make the same mistake twice. It sounds like you’ve done that and arrived at an investing strategy that works for you. My biggest investing mistake was not in stocks, but a venture that a family member proposed to me. I didn’t do my research and after I invested a lot of money, it turned out to be a fraud. Always research first and act second!

    1. Hi Gary,

      Yes, always research first and act second. A mistake is often a good think as long as we don’t repeat it.

      Your example is a very good one. A lot of the the time we don’t think as we much when it’s coming from the family. We simply trust too much. Sorry about your experience.

      Thanks for stopping by :)

  3. Hi Poor Swiss, I was surprised not to see any of my major investing mistakes on your list! Relying too heavily on broker recommendations and forecast in the early days was one (probably similar to your #8), but my biggest was getting over-confident after a few successful investments and taking far too much risk / concentration in one or two specific stocks.

    I’ve been investing for over 20 years now but still keep learning from new mistakes! At least they seem to be getting a little smaller over time…

    Cheers, Frankie

    1. Hi Frankie,

      Fortunately for me, I didn’t do any major investing mistake that cost me money. The cost was more in lost opportunity for me. Fortunately too, I never started with individual stocks. Even if I selected expensive funds, it’s still better than if I had selected very bad stocks.

      I’m glad your mistakes are getting smaller :) I’m far from having invested for 20 years, but I’m sure I’ll do many mistakes (and learn from them) in the coming years.

      Good luck with your investments! Thanks for stopping by.

  4. Investing can be simple or extremely complex. I have found that a simple portfolio of index funds is best for me. I do not have access to the required information to try to compete with professional investors. If I receive average market returns, I will out perform 80% of the investors who are trying to beat the market.

    1. Hi Dave,

      Once I realized my various mistakes, I now agree with you that a very simple portfolio of index funds (ETFs or mutual funds) is the best. Average market returns are what we should all trying to achieve. Minimizing the fees to get as close as possible to the market returns.

      Thanks for stopping by :)

  5. Really solid advice. I feel like most lists like this are pretty far off the mark, or they’re repeating advice that’s been run into the ground, but these were excellent.

    I feel right now the whole “Not investing early enough” hit the hardest. I feel I’d have more confidence in investing if I started earlier, which I think is pretty important.

    Found my way over here from The Fire Lane’s “Writing that Wowed Me” list. Was not disappointed. ;)

    1. Hi Elise,

      Thanks a lot :)

      If my list was excellent, it means my mistakes were excellent :P
      I’m glad you liked the post though ;)

      Yes, I really wish I would have invested earlier and kept invested!

      Thanks for stopping by :)

  6. We see biggest stocks rally in recent decade. I am really worried what is bigger risk – try to time the market, or keep investing into this bubble (?) market.

    1. Hi RJ,

      Yes, stocks are at an all-time high. However, they have been at an all-time high many times where it was still interesting to invest.

      Personally, I am keeping investing. But I understand your concerns. You may want to try more conservative allocation with bonds maybe?

      Thanks for stopping by.

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