The COVID-19 crisis highlights a golden rule of investing 

It’s a golden rule of investing, and the spread of COVID-19 illustrates its importance, especially as I don’t think markets are close to bottom yet.

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.

Pity the individual who chose to begin their investment journey a few weeks ago. Especially pity them if they had a big lump sum and invested it all. 

Don’t get me wrong, I’m sure the markets will recover, eventually. But this situation does illustrate a golden rule of investing — never throw all your money at the stock market in one go.

Actually, on thinking about it, I would not pity an investor who has just begun their investment journey if they had followed this rule — I would envy them.  

The markets have further to fall

Already we have seen a share rout, followed by a mini recovery, and then further falls. The mini recovery saw many conclude that shares had hit bottom, that ‘now was a time to buy.’

Such false dawns are common occurrences during stock market crises. The infamous 1929 crash saw many short-lived recoveries which tempted shareholders back in.

COVID-19 is spreading exponentially. It makes most of us nervous about our own health and the health of loved ones — is that a seasonal cold, or the dreaded virus? We wouldn’t be human if those thoughts didn’t cross our minds every time there’s a sneeze. 

I believe the markets are underestimating the likely spread of the virus and its economic impact. They always are lousy at judging something that changes exponentially. Maybe it’s in our genes — Ray Kurzweil, the famous futurologist and Google’s Director of Engineering has said that our evolutionary past means we have no instinctive understanding of exponential — we might get it intellectually, but not in our gut. 

As the virus spreads, we will change our behaviour, employers may eventually become more nervous about workers spreading the virus than about lost production, and markets will fall a lot further.

As for predicting the recovery, getting the timing right is nigh on impossible.

Diversify over time

That is why diversification over time is so important. If you plough all your money into stocks in one go, you risk timing your investment with stock market falls. 

Sure, if you sit tight you will probably regain your money eventually, but you can do better.

If, instead, you drip feed your money into the market — say once a month for three years, or once every three months, you are limiting the risk while increasing the chances that that you will benefit from a recovery.

Three different situations, same response

Let’s say that you were savvy enough to have liquidated your portfolio at market peak, you have a lump sum for some other reason, or you invest a proportion of your income every month.

I would say spread out your investment over three years. If you invest a proportion of your income every month, then relax, you are following that strategy by default.

Follow that approach and just as investment losses occur on the falls, profits will accrue on the rises. 

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

Investing Articles

Will the S&P 500 crash in 2026?

The S&P 500 delivered impressive gains in 2025, but valuations are now running high. Are US stocks stretched to breaking…

Read more »

Teenage boy is walking back from the shop with his grandparent. He is carrying the shopping bag and they are linking arms.
Investing Articles

How much do you need in a SIPP to generate a brilliant second income of £2,000 a month?

Harvey Jones crunches the numbers to show how investors can generate a high and rising passive income from a portfolio…

Read more »

Investing Articles

Will Lloyds shares rise 76% again in 2026?

What needs to go right for Lloyds shares to post another 76% rise? Our Foolish author dives into what might…

Read more »

Investing Articles

How much passive income will I get from investing £10,000 in an ISA for 10 years?

Harvey Jones shows how he plans to boost the amount of passive income he gets when he retires, from FTSE…

Read more »

Investing Articles

Down 34% in 2025 — but could this be one of the UK’s top growth stocks for 2026?

With clarity over research funding on the horizon, could Judges Scientific be one of the UK’s best growth stocks to…

Read more »

piggy bank, searching with binoculars
Investing Articles

Can the rampant Barclays share price beat Lloyds in 2026?

Harvey Jones says the Barclays share price was neck and neck with Lloyds over the last year, and checks out…

Read more »

Investing Articles

Here’s how Rolls-Royce shares could hit £25 in 2026

If Rolls-Royce shares continue their recent performance, then £25 might be on the cards for 2026. Let's take a look…

Read more »

Departure & Arrival sign, representing selling and buying in a portfolio
Investing Articles

Prediction: in 2026 the red-hot Rolls-Royce share price could turn £10,000 into…

Harvey Jones can't believe how rapidlly the Rolls-Royce share price has climbed. Now he looks at the FTSE 100 growth…

Read more »