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There’s no reason you should lose money investing in stocks, considering that the markets always move higher over time. This decade alone, the S&P 500 has risen by about 88%.

Just investing in an S&P 500 fund could have helped any investor generate solid profits. But a lot of investors still take a beating on Wall Street because they make common mistakes that can be easily avoided.

Here are the top mistakes Americans make when investing in the stock market, according to three financial experts contacted by GOBankingRates.

Also see the No. 1 mistake Americans make with their Roth IRAs, according to experts.

Misjudging risk was cited by Christine Chase, vice president and financial consultant at Fidelity Investments. More precisely, she cited a tendency to misjudge risk tolerance, which means too many investors either take on too much risk or are too conservative. Both extremes can negatively impact your return.

“Excessive risk can lead to emotional decision-making and panic-selling during market downturns, while being too conservative may prevent your portfolio from growing enough to meet long-term goals or keep pace with inflation,” Chase said.

To help manage risk and navigate the market’s ups and downs, she recommended maintaining a well-diversified portfolio and working with a financial professional.

Anthony Grosso, a New York-based financial strategist and mortgage loan originator, told GOBankingRates the biggest mistake he sees people make is “blindly trusting the news” when investing. He learned this lesson himself as a younger investor.

“What I learned fast is that by the time something makes [it to the news], the market has already reacted,” Grosso said. “The news isn’t meant to educate — it’s there to get clicks and views. They will spin a story, beat a topic to death until you’re panicked or euphoric, and both of those times are when you make emotional decisions which are the worst ones.”

If you do watch the news, he recommended doing so with a healthy dose of skepticism.

“Try to get reports of the actual data — not someone’s opinion on the data,” Grosso said. “Learn to make your own opinions and it will give you the confidence to have a plan and stick with it.”

Not cutting losses is a mistake that happens a lot, according to Edward Corona, a Florida-based trader and publisher of The Options Oracle Newsletter. In fact, it happened to him early in his career.

“I’d hang onto trades way too long, convincing myself they’d bounce back,” Corona told GOBankingRates. “I’d look at charts, squint real hard, and try to find a reason to stay in. You know the drill: ‘It’s just a dip,’ or ‘I’m down, but not that much…’”

The problem, he said, is that small losses can “turn into portfolio wreckers real fast” if you stay with a sinking stock too long. His suggestion is to have a plan in place before hitting the “buy” button and sticking with that plan when an investment goes south.

“I’m going to have a predetermined ‘stop loss’ and ‘take profit’ level before I enter the trade, which would be based on a support level,” Corona said. “If it breaks below that level, I will exit the trade and redeploy the capital elsewhere.”