5 classic but costly stock market clangers to avoid!

Our writer hopes avoiding this handful of common stock market pitfalls can improve his long-term investment returns and financial health.

The content of this article was relevant at the time of publishing. Circumstances change continuously and caution should therefore be exercised when relying upon any content contained within this article.

You’re reading a free article with opinions that may differ from The Motley Fool’s Premium Investing Services. Become a Motley Fool member today to get instant access to our top analyst recommendations, in-depth research, investing resources, and more. Learn More.

Bus waiting in front of the London Stock Exchange on a sunny day.

Image source: Getty Images

Investors have been making the same stock market mistakes for decades. Here’s a handful of errors I try to avoid!

1. Becoming emotionally attached

A share is a stake in a business. Buying or selling one therefore ought to be a rational decision.

Becoming emotionally attached to a particular position, for example because it was the first share one ever owned, can be a financially costly mistake.

2. Ignoring inconvenient signs

A common form of what psychologists call ‘cognitive dissonance’ is a confirmation bias. In everyday life, we have all experienced this when someone says “you only hear what you want to hear!”

This is dangerously common in investing too.

Take my shareholding in boohoo. Since I bought it around a year ago, the shares have continued to fall. With each piece of news, I wonder whether the worst is yet over – or still to come. Having spent money on boohoo shares, I have a natural instinct to hope for the best. But hope is not an investing strategy.

Ignoring signs about the likely valuation of a share just because they do not fit with one’s investment thesis is a mistake.

3. Too much of a good thing

As an investor, I find it a helpful discipline to identify what I think is my single best idea at any one time.

So, if I came into a windfall tomorrow and wanted to invest it, would I put it straight into my current best idea? Not necessarily. In the stock market, certainly, one can have too much of what seems like a good thing. Even the best run company can stumble, sometimes dramatically and without prior warning.

Lacking sufficient diversification is a classic investing mistake. When it costs, it can cost a lot.

4. Skipping the complex stuff

Some companies use complicated language, unusual financial metrics or opaque accounting techniques.

There are various reasons why a firm may employ such jargon or methodology. But as an investor, what matters to me is whether I can confidently value a business. If not, I cannot judge whether its shares offer me good value.

So when faced with complex corporate information, I normally do one of two things.

Either I take that as a red flag in itself and stop researching the firm, or else I dig in to learn more. Simply skipping complex parts of a company’s reports and stock market announcements because I do not understand them is a recipe for financial disaster!

5. Ignoring personal experience

Personal experience can add useful context on top of what a company reports to the stock market.

For example, one reason I continue to hold J D Wetherspoon shares despite their weak performance is because every time I go into a Spoons pub, it is heaving. Yes, the business faces ongoing challenges with inflation. But my personal observation makes me think it still has the foundations of a successful company.

However, what if a company seems to be doing well, but my personal experience is at odds with that? I would not ignore my personal experience. I would do more research to understand whether it might be part of a wider issue that could affect the investment case for a company.

C Ruane has positions in Boohoo Group Plc and J D Wetherspoon Plc. The Motley Fool UK has recommended Boohoo Group Plc. Views expressed on the companies mentioned in this article are those of the writer and therefore may differ from the official recommendations we make in our subscription services such as Share Advisor, Hidden Winners and Pro. Here at The Motley Fool we believe that considering a diverse range of insights makes us better investors.

More on Investing Articles

Woman riding her old fashioned bicycle along the Beach Esplanade at Aberdeen, Scotland.
Investing Articles

4 reasons the Rolls-Royce share price might be headed to £24

Could the Rolls-Royce share price double from around £12 to closer to £24? Here are a few reasons why it…

Read more »

Young woman working at modern office. Technical price graph and indicator, red and green candlestick chart and stock trading computer screen background.
Investing Articles

Down 23%, consider this FTSE 250 share that’s boosted profit forecasts!

This FTSE 250 tech share's leapt 8% on Wednesday (18 March) after it raised full-year profit forecasts. Is now the…

Read more »

Passive income text with pin graph chart on business table
Investing Articles

How much passive income can you earn by investing £20,000 in a Stocks and Shares ISA?

With dividend yields up to 10%, REITs might be some of the top passive income opportunities for UK investors in…

Read more »

Group of friends meet up in a pub
Investing Articles

Diageo shares are back at 2012 levels. Time to consider buying?

Diageo shares have fallen around 65% from their highs and now trade at levels not seen for well over a…

Read more »

Investing Articles

Softcat: a FTSE 250 tech stock offering growth, dividends and value

Right now, the share price of FTSE 250 IT company Softcat is well off its highs. And at current levels,…

Read more »

Black woman using smartphone at home, watching stock charts.
US Stock

3 huge pieces of news that could impact the Nvidia share price

Jon Smith talks through some key reveals and implications for the Nvidia share price from the company conference taking place…

Read more »

Three signposts pointing in different directions, with 'Buy' 'Sell' and 'Hold' on
Investing For Beginners

This FTSE stock is now trading at the lowest level since the 1990s! Should I buy?

Jon Smith explains why a FTSE share is currently at multi-decade lows and might surprise some with his decision on…

Read more »

Businessman with tablet, waiting at the train station platform
Investing Articles

Down 21% in less than 2 months, this FTSE small-cap stock’s worth a look today

Despite rising 8% yesterday, this 177p growth stock from the FTSE AIM 100 Index is significantly lower than where it…

Read more »