Common Mistakes New Investors Should Avoid

13 October 2026

Tolu was twenty-six, three months into his first real salary, when he decided he was tired of watching other people make money. His cousin had doubled his capital on one stock. A friend's WhatsApp status was a wall of green screenshots. So one Friday evening, Tolu opened a brokerage app, typed in a ticker he had heard twice that week, and bought with the money he had set aside for his house rent.

By Monday he was up 6%, and he felt like a genius. A month later he was down 30%, checking his phone at 2 a.m., and wondering if investing was only for other people.

Tolu is a composite character, but his story is a familiar one. Nothing that happened to him was bad luck. It was a handful of mistakes that almost every beginner makes, often in the same order. The good news is that these errors are predictable, which means you can skip most of them. Here are the seven that matter most.

1. Investing Money You May Need Soon

Share prices move up and down in the short run, and they do not wait for your emergencies. If the money you invest is meant for rent, school fees or a hospital bill, one badly timed dip can force you to sell at a loss. Time is what makes market swings survivable, and money with a deadline has none.

What to do instead: Build an emergency fund first, enough to cover several months of basic expenses, and keep it somewhere accessible. Invest only what you can leave alone for years, so a bad month never forces your hand.

2. Buying on Tips and Hype

WhatsApp groups, social media pages and well-meaning friends are full of "sure" stocks. The trouble is timing. By the time a tip reaches you, the price has often already jumped, and the people who shared it may be looking for someone to sell to. A crowd's excitement is not research.

What to do instead: Before buying anything, answer three questions in plain words. What does this company sell? How does it make money? Why is the price what it is today? If you cannot answer in two sentences, you are not investing yet, you are gambling on someone else's confidence.

3. Falling for the Headline Number

A big percentage in a headline can hide what actually produced it. Take Airtel Africa, whose profit after tax rose from $328M to $813M, a jump of 147%. A large part of that came from currency accounting: a $127M foreign exchange gain this year against a $179M loss the year before, a swing of about $306M on paper. Strip out currency effects and one-offs, and underlying profit grew about 86%. Still strong, but a different story.

What to do instead: When you see a dramatic figure, ask what produced it. Growth that comes from customers and operations tends to repeat. Growth that comes from accounting swings often does not.

4. Putting Everything in One Basket

You can study a company carefully, trust its management and still be surprised. A new regulation, a bad quarter or a scandal can hit even a strong business, and you rarely get to choose when. If most of your money sits in one stock, one surprise decides your whole result.

What to do instead: Spread your money across several companies and different sectors, and consider funds that already hold many stocks at once.

5. Selling in a Panic

A falling price hurts, but it only becomes a loss when you sell. Many beginners sell near the bottom because the red numbers feel unbearable, then watch prices recover and buy back in higher. That turns a temporary dip into a permanent loss, and it is far more costly than the dip itself.

What to do instead: Decide, before you buy, how much of a drop you can sit through, and write down why you bought. When prices fall, ask one question: has the reason I bought changed, or only the price? Also, check your portfolio less often. Watching it every hour will not improve it, it will only improve your anxiety.

6. Chasing Returns That Sound Too Sweet

Promises of guaranteed monthly profits of 20% or 30% are the oldest trap in the book, and Nigerians have seen them many times, from MMM to newer platforms with fresh logos and the same script. Real investments rise and fall, and no honest seller can guarantee a fixed, huge return. Early payouts in these schemes are often funded by newer members, which is exactly why they feel so convincing.

What to do instead: Treat guaranteed high returns as a warning sign, not an invitation. Before handing over money, check whether the platform and the people selling it are registered with the Securities and Exchange Commission (SEC) Nigeria. If you cannot verify them, walk away, however good the screenshots look.

7. Having No Plan, and Ignoring the Quiet Costs

Without a goal, every decision is a guess. People who trade constantly with no purpose also pay for the habit: every buy and sell carries brokerage charges and levies that chew steadily into profit. On the other side, money left idle in an account that earns almost nothing loses value as prices rise. Neither approach feels dramatic, yet both slowly lose ground.

What to do instead: Ask yourself the following questions: What are you investing for, and when will you need the money? How much will you add each month? What will you buy, and when will you review it? Then keep an eye on costs and on inflation, because a return only counts after both have taken their share.

Start Small, Stay Steady

After his rough first month, Tolu stopped chasing tips and started asking questions. He rebuilt his emergency fund, wrote a short plan, chose a few companies he could explain to a friend in two sentences, and began adding a fixed amount each month. He is not rich yet, but he sleeps well.

That is the quiet truth about investing: the people who do well are rarely the boldest. They are the ones who avoided the big, avoidable mistakes long enough for time to work.

Before your next investment, run through this checklist:

• Is this money safe to leave alone for years?
• Can I explain what the company does and why I am buying?
• Do I know what is behind the headline number?
• Is my money spread out enough that one bad day will not break me?
• Have I decided in advance how I will react to a drop?
• Is the return realistic, and is the seller registered?
• Do I have a written plan, and do I know the costs?