Is Your Portfolio Making These Common Mistakes?

Building a portfolio is not only about choosing investments. It is also about avoiding decisions that can quietly increase your risk or reduce your returns.

Some mistakes are easy to notice, such as buying a stock without researching the company. Others develop gradually. One investment becomes too large, fees accumulate or an investor keeps changing direction whenever the market moves.

A portfolio does not need to be perfect. It needs a clear purpose, a suitable level of risk and a process for reviewing decisions over time.

Here are some of the most common portfolio mistakes and how to recognise them.

Mistake 1: Investing without a clear goal

A portfolio should be built around a financial goal.

You may be investing to:

• Build wealth over many years
• Prepare for retirement
• Generate regular income
• Save for education
• Make a future purchase
• Preserve part of your savings

Different goals may require different investments.

For example, an investor saving for retirement in 25 years may be able to accept more short-term market volatility. Someone who needs the money next year may not have enough time to recover from a major decline.

Before selecting an investment, ask:

• What is this money for?
• When might I need it?
• How much loss can I realistically accept?
• Do I need income or long-term growth?
• Does this investment match my Shariah requirements?

Without a clear goal, it becomes difficult to decide whether an investment belongs in your portfolio.

Mistake 2: Investing money you may need soon

Stocks and other market investments can fall in value, sometimes suddenly.

If you invest money needed for rent, essential bills or an upcoming expense, you may be forced to sell during a market decline.

Imagine investing $5,000 that you expect to use for a payment in six months. If the portfolio falls by 20%, you would have only $4,000 when the money is needed.

An emergency fund can help separate short-term needs from long-term investments. It may reduce the risk of selling investments at an unfavourable time when an unexpected expense occurs.

Before investing, consider whether you can leave the money untouched for the planned period.

Mistake 3: Putting too much in one investment

A company can appear successful and still face unexpected problems.

Its profits may fall, a new competitor may emerge or its industry may be affected by regulation or changing technology.

If one company represents most of your portfolio, its problems become your problems.

Concentration can also exist when you own:

• Several stocks from the same industry
• Multiple ETFs with similar holdings
• Investments focused on one country
• A large amount of stock in your employer
• Different products linked to the same asset

Diversification spreads money across investments with different sources of risk and return.

It cannot prevent every loss, but it can reduce the effect of one company or sector performing badly.

Mistake 4: Buying what recently performed well

A stock, sector or fund that has risen sharply can attract attention. Investors may buy because they fear missing further gains.

This is known as chasing performance.

Past performance tells you what already happened. It does not tell you with certainty what will happen next.

A rising investment may continue to perform well, but it may also have become expensive or popular for reasons that cannot last.

Before buying, ask:

• What caused the recent increase?
• Has the company’s financial performance improved?
• Does its current price reflect unrealistic expectations?
• Am I buying because of research or excitement?
• Would I still choose it if its recent return were lower?

A strong recent chart should be a reason to investigate, not a substitute for research.

Mistake 5: Reacting emotionally to market movements

Market declines can feel frightening. Rapid gains can create excitement and overconfidence.

Both emotions can lead to poor decisions.

An investor may sell after prices fall because they fear further losses. They may then buy again only after prices recover, turning a temporary decline into a permanent loss.

Another investor may take excessive risk after several successful trades and assume that recent gains prove their strategy will continue working.

A written plan can help reduce emotional decisions. It may state:

• Your investment goal
• Your target portfolio mix
• How often you will invest
• When you will review the portfolio
• What conditions would justify selling an investment

A market movement alone does not always mean your plan needs to change. Check whether the investment’s underlying reason has changed.

Mistake 6: Trading too frequently

Frequent activity can make an investor feel in control, but more trades do not automatically produce better results.

Repeated buying and selling may create:

• Transaction fees
• Bid-ask spread costs
• Currency conversion costs
• Tax consequences
• Greater exposure to short-term price movements
• More opportunities for emotional mistakes

Even when a platform charges no commission, trading may still involve other costs.

Before placing a trade, ask what has changed since your original decision. A new headline or small price movement may not justify changing a long-term portfolio.

Regular investing and patient ownership may be more appropriate for some goals than trying to respond to every market movement.

Mistake 7: Ignoring fees

Fees may appear small, but they reduce the amount of money remaining in your portfolio to generate future returns.

Possible costs include:

• Trading commissions
• Custody fees
• Fund expense ratios
• Advisory fees
• Currency conversion charges
• Bid-ask spreads
• Withdrawal or transfer fees

Suppose two funds follow similar investments. One charges an annual fee of 0.25%, while the other charges 1%.

The difference may look small in one year. Over a long period, however, the higher fee can have a much larger effect because money paid in fees is no longer invested.

A lower fee does not automatically make an investment better. The fund’s holdings, strategy, risk and performance also matter.

Compare total costs between similar products and understand what you are paying for.

Mistake 8: Owning investments you do not understand

An investment may be popular, but that does not mean it is suitable for you.

Before buying, you should understand:

• What you own
• How it may generate a return
• What could cause it to lose value
• How easily it can be sold
• What fees apply
• Whether it uses borrowing or complex financial instruments
• Whether it meets your Shariah requirements

This also applies to ETFs. A fund may hold unfamiliar assets, focus on a narrow theme or use a strategy that increases both gains and losses.

If you cannot explain an investment in simple terms, research it further before adding it to your portfolio.

Mistake 9: Never rebalancing

Investments do not grow at the same rate. Over time, your portfolio may move away from its original plan.

Suppose your target portfolio contains:

• 60% stocks
• 20% sukuk
• 10% gold
• 10% savings

After a strong period for stocks, they may rise to 75% of the portfolio. You now have more stock risk than you originally intended.

Rebalancing means adjusting the portfolio to bring it closer to its target mix.

This may involve:

• Adding new money to underrepresented assets
• Reducing an investment that has become too large
• Reviewing overlapping funds
• Removing holdings that no longer match your goals

Rebalancing does not require changing your portfolio every day. You can review it periodically or when an asset moves significantly away from your planned allocation.

Consider fees, taxes and other consequences before selling.

Mistake 10: Failing to review Shariah compliance

Shariah compliance is not always permanent.

A company may change its business activities, increase its interest-bearing debt or report more income from non-permissible sources.

An ETF may also change its holdings.

An investment that passed a Shariah screen when you bought it may receive a different result after new financial information becomes available.

Regularly check:

• The latest compliance status
• The date of the screening result
• Any change notifications
• Whether purification is required
• What action is needed if the investment becomes non-compliant

Diversification cannot make a non-compliant investment permissible. Each holding should meet the applicable Shariah requirements.

Mistake 11: Checking prices but not progress

A portfolio may rise or fall over a short period without telling you whether your overall plan is working.

Instead of checking only daily prices, review:

• Your progress towards the financial goal
• The amount you are contributing
• Your overall return after fees
• Your current asset allocation
• The risk level of the portfolio
• Any changes in your time horizon or financial situation
• The continuing purpose of each investment

Compare investments with suitable benchmarks. A stock should usually be compared with similar companies or an appropriate market index, not with an unrelated asset.

The purpose of a portfolio review is not to find a reason to trade. It is to confirm that the portfolio still matches your plan.

A simple portfolio check-up

You can review your portfolio by asking seven questions:

• Does every investment support a clear goal?
• Could I leave this money invested for the required period?
• Is too much of my portfolio dependent on one company or industry?
• Do I understand every investment I own?
• Are the fees reasonable for what I receive?
• Does my current portfolio still match my intended level of risk?
• Is every holding still Shariah-compliant?

If you cannot answer one of these questions, identify what information or change is needed before making another investment.

Good portfolio management is often less about constantly finding new opportunities and more about maintaining a clear, suitable and disciplined plan.

Quiz

Question 1

Why can chasing a recently successful investment be risky?

• A. Its recent performance guarantees that the price will fall
• B. Past gains do not guarantee future results, and the investment may have become expensive
• C. Successful investments cannot be researched

Correct answer: B

Recent performance shows what has already happened. Investors should examine the reasons for the increase, the investment’s value and its future risks before buying.

Question 2

Your target stock allocation is 60%, but it has grown to 75% of your portfolio. What may help restore your intended risk level?

• A. Rebalancing the portfolio
• B. Ignoring the change permanently
• C. Buying more of the same stocks

Correct answer: A

Rebalancing adjusts the holdings to move the portfolio closer to its planned asset mix.

Question 3

Which is the best reason to review a portfolio?

• A. To make a trade every time prices move
• B. To copy the latest investment trend
• C. To check whether the holdings still match your goals, risk level and Shariah requirements

Correct answer: C

A portfolio review helps confirm that your investments still support your plan. It does not always mean that you need to buy or sell.

Sources

• https://www.investor.gov/introduction-investing/getting-started/understanding-fees
• https://www.investor.gov/introduction-investing/general-resources/news-alerts/alerts-bulletins/investor-bulletins/updated
• https://www.investor.gov/introduction-investing/general-resources/news-alerts/alerts-bulletins/investor-bulletins/ten-investment-tips-2025-investor-bulletin
• https://www.investor.gov/additional-resources/general-resources/publications-research/info-sheets/beginners-guide-asset
• https://www.finra.org/investors/insights/tips-new-investors
• https://www.finra.org/investors/insights/concentration-risk
• https://www.finra.org/investors/insights/active-passive-investing
• https://www.finra.org/investors/insights/investment-returns
• https://www.finra.org/investors/insights/your-brokerage-statement-how-read-and-make-sense-it
• https://www.investor.gov/introduction-investing/general-resources/news-alerts/alerts-bulletins/investor-bulletins/mutual-fund-and-etf-fees-and-expenses-investor-bulletin

Frequently asked questions

Why can chasing a recently successful investment be risky?

Past gains do not guarantee future results, and the investment may have become expensive. Examine the reasons for the increase, the investment’s value and its future risks before buying.

What does portfolio rebalancing involve?

Rebalancing means adjusting the portfolio to bring it closer to its target mix. This may involve adding new money to underrepresented assets, reducing an investment that has become too large, reviewing overlapping funds or removing holdings that no longer match your goals.

Why should Shariah compliance be checked regularly?

A company may change its business activities, increase its interest-bearing debt or report more income from non-permissible sources. An ETF may also change its holdings, and new financial information may lead to a different screening result.

Does a portfolio review always require a trade?

No. The purpose of a portfolio review is to confirm that the portfolio still matches your goals, risk level and Shariah requirements, not to find a reason to trade.

How can small fees affect long-term portfolio value?

Fees reduce the amount of money remaining in your portfolio to generate future returns. Over a long period, higher fees can have a much larger effect because money paid in fees is no longer invested.

Related terms

• Halal Investing