My 3 biggest investing mistakes and how I made myself richer!

If I could go back in time to change my investing future, these are the lessons I would drum into my younger self, says Tom Rodgers.

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.

The three biggest investing mistakes I see people make seem obvious to me now. I wish I could grab every one of you and give you a shake!

It really is easy to enrich yourself once you’ve got a bit of experience under your belt, so let’s dive in.

Not investing consistently

I thought I’d just add money to my Stocks and Shares ISA whenever I could. That was my 2010 New Year’s Resolution. These tax-efficient accounts had already been around since 1999, introduced by then-Labour Chancellor Gordon Brown.

Of course it didn’t happen. Because I didn’t make the effort to set up a Direct Debit to my Stocks and Shares ISA, the money I hoped I would set aside just disappeared on frivolous purchases.

When you don’t invest consistently you lose the ability to make the most of what is called ‘pound-cost averaging’. Invest at set regular intervals and you can buy shares in your favourite high-yield companies when the price is low, as well as when it has appreciated a little.

This stops you from overpaying with a single lump sum when share prices are high.

No one wants to pay more than something is worth. Imagine going to a restaurant and the manager sees you coming, and puts up the price of a steak from £12 to £40 because they’re busy. The same principles applies here. If I’d just fed a regular sum into my Stocks and Shares ISA over a long period, I would have gotten a better average price for my shares.

Buying and selling too often

One piece of advice I wish I’d known sooner was to ‘run the winners’. That means not taking small profits from shares that have appreciated in value in the short term. The power of compound interest means you are much likely to get richer if you make good purchases and let them sit for the long term.

Not diversifying enough

Diversifying your portfolio — the funds or stocks you hold in your Stocks and Shares ISA — means you are more protected against a big fall in one sector, like manufacturing or financial services.

One common investing mantra is to invest in what you know. As a wet-behind-the-ears investor, I thought I was being clever by only buying shares in video games companies. But a single piece of legislation, a tax break that gets slashed or any other regulatory change can see profits fall in your favourite businesses and the share price dive along with it.

If I had my time again I would have spent my first few thousand pounds buying top high-yield funds instead of individual company shares. Funds like the popular iShares UK Dividend UCITS ETF, which pays out 5.75% a year at current prices, track the performance of lots of different high-paying companies. This gives you instant diversification to many sectors and protects you against a plunge in any one area.

Ask any older investor what their biggest regret is, and they’ll likely tell you they wished they had started investing sooner. Once you see compound interest at work, it becomes self-evident that the longer you let your money work for you, the richer you will become.

Views expressed 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

British flag, Big Ben, Houses of Parliament and British flag composition
Investing Articles

Back above 10,000! Is the FTSE 100 index on track again?

The FTSE 100 index has been yo-yoing up and down with the latest news headlines around the oil crisis. Where…

Read more »

Finger clicking a button marked 'Buy' on a keyboard
Investing Articles

Stock market correction: Is there still time to buy UK shares cheap?

Long-term investors can do well to stay calm through stock market corrections, and even crashes, and pick up shares when…

Read more »

Warm summer evening outside waterfront pubs and restaurants at the popular seaside resort town of Weymouth, Dorset.
Investing Articles

2 FTSE 100 blue-chips to consider for a new £20k Stocks and Shares ISA

Ben McPoland highlights a pair of high-quality FTSE 100 stocks that have strong momentum on their side yet are trading…

Read more »

Young Caucasian woman with pink her studying from her laptop screen
Investing Articles

Are depressed Lloyds shares just too tempting to miss now?

Lloyds shares are coming under renewed pressure as conflict in the Middle East threatens the fragile global economic recovery.

Read more »

Female student sitting at the steps and using laptop
Investing Articles

7 FTSE 100 shares that look cheap after the 2026 stock market correction

Falling stock markets often present bargain opportunities. Let's take a look at some of the cheapest FTSE 100 shares at…

Read more »

piggy bank, searching with binoculars
US Stock

Up 59% this year, this S&P 500 stock is smashing the index!

Jon Smith points out a stock from the S&P 500 that's flying right now as part of a transformation plan,…

Read more »

Businessman hand stacking money coins with virtual percentage icons
Investing Articles

Stock market correction: a rare second income opportunity?

Falling share prices are pushing dividend yields higher. That makes it a good time for investors looking for chances to…

Read more »

Finger clicking a button marked 'Buy' on a keyboard
Dividend Shares

I just discovered this REIT with a juicy 9% dividend yield

Jon Smith points out a REIT that just came on his radar due to the high yield, but comes with…

Read more »