3 stock market mistakes I’d avoid

Our writer explores a trio of things that can trip up investors who are new to the stock market. Each can shred wealth rather than build it.

| More on:

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.

Young Caucasian girl showing and pointing up with fingers number three against yellow background

Image source: Getty Images

All stock market investors make mistakes, no matter how experienced. Warren Buffett famously lost a fair bit of money investing in Tesco, which he admitted was “a huge mistake“.

The key is to minimise costly rookie errors as time goes on. Here are three that stand out to me.

1. Not researching a stock

Many people behave differently with their money in the stock market than they would in other situations.

Investor Peter Lynch captured this perfectly in the quote below:

The public, when they buy a refrigerator, they go to consumer reports. They buy a microwave oven, they do that kind of research…They do research on apartments…But people hear a tip on a bus on some stock and they’ll put half their life savings in it before sunset.

Peter Lynch

Putting money in a stock without doing much (or any) research is gambling, not investing. It’s a recipe for losing money.

If I don’t know how to do basic stock research, that’s okay. There’s an ocean of material online to help me learn, including here at The Motley Fool.

2. Trying to time the market

The second mistake I’d avoid is trying to time the market. There’s a wealth of research that proves most day traders lose money. The market is just too unpredictable.

Consider this: between 2004 and 2023, seven of the S&P 500‘s best 10 days fell within two weeks of the 10 worst days, according to JP Morgan.

The chart below compares an individual who was fully invested over that time to investors who missed some of the best days as a result of being temporarily out of the market.

Source: JP Morgan Asset Management (chart adapted)

As we can see, missing the 10 best days would have reduced the final portfolio value by more than half — from $63,637 down to just $29,154!

This proves the old adage that “time in the market beats timing the market“. This is a core part of long-term — i.e. Foolish — investing.

3. Selling a stock too soon

For many investors, the most painful experience isn’t failing to identify an incredible stock or watching a dud crash and burn. Instead, it’s likely selling a winning company far too soon.

Take Amazon (NASDAQ: AMZN), for example. Back when the internet started to take off, a family member of mine was amazed at the sheer selection of books on Amazon (it started as an online bookseller). He was so impressed that he bought some shares.

You can probably guess what happened next. Yep, he sold those shares not long after, banking a bit of profit.

Today, the stock is at a record high after rising 10,360% in 20 years. The missed gains are enormous.

Thing is, Amazon has never given long-term investors a genuine reason to sell. It’s relentlessly captured growth markets, from e-commerce to cloud computing and now digital advertising.

Amazon’s revenue is expected to reach $638bn this year, then top $1trn by 2030!

Alas, I’ve never owned the stock, and I think it being broken up is a risk as the tech giant gets ever larger.

But the point still stands. If I sell a quality stock in its third year, and miss out enjoying its 23rd year, then I’m potentially leaving untold riches on the table.

JPMorgan Chase is an advertising partner of Motley Fool Money. John Mackey, former CEO of Whole Foods Market, an Amazon subsidiary, is a member of The Motley Fool’s board of directors. Ben McPoland has no position in any of the shares mentioned. The Motley Fool UK has recommended Amazon and Tesco 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

Asian man looking concerned while studying paperwork at his desk in an office
Investing Articles

A stock market crash feels like it might be imminent

Conflict in the Middle East means a stock market crash feels like a real possibility right now. But being ready…

Read more »

Rolls-Royce's Pearl 10X engine series
Investing Articles

Should I buy Rolls-Royce shares as they march ever higher?

Rolls-Royce is making billions of pounds a year and looks set to do even better in future -- so what's…

Read more »

Smiling family of four enjoying breakfast at sunrise while camping
Investing Articles

£1,000 buys 110 shares in this UK beverage stock that’s smashing Diageo 

Shares of Tanqueray-maker Diageo are languishing at multi-year lows. So why is the stock behind this tonic water brand on…

Read more »

UK financial background: share prices and stock graph overlaid on an image of the Union Jack
Investing Articles

What next for Aviva shares after a cracking set of 2025 results?

Aviva achieving its 2026 financial goals a year ahead of schedule has got to be good for the shares... oh,…

Read more »

This way, That way, The other way - pointing in different directions
Investing Articles

Should I buy stocks or look to conserve cash right now?

In a market dealing with AI uncertainty and conflict in the Middle East, should investors be looking for stocks to…

Read more »

Investing Articles

Here’s how many British American Tobacco shares it takes to earn a £1,000 monthly second income

Is an AI-resistant business with a 5.38% dividend yield a good choice for investors looking for a second income in…

Read more »

Black woman using smartphone at home, watching stock charts.
Investing Articles

1,001 Barclays shares bought 12 months ago are now worth…

Barclays shares have delivered excellent returns over the last year. But can the FTSE 100 bank keep outperforming? Royston Wild…

Read more »

Two business people sitting at cafe working on new project using laptop. Young businesswoman taking notes and businessman working on laptop computer.
Investing Articles

Get started on the stock market: 3 ‘safe’ shares for beginner UK investors to consider

Kicking off an investment portfolio on the stock market may seem like a scary prospect. Mark Hartley details a few…

Read more »