Investors move markets based on what they expect to happen in the future. If you've read enough about the incoming administration or the state of artificial intelligence or the historical economic impact of tariffs, you may think you have a pretty good idea of what's coming over the next four years.

But if you plan on calibrating your portfolio according to your assumptions, you could be falling into a classic investor trap, says Ryan Detrick, chief market strategist at the Carson Group. The reality is, it's rarely easy to draw a straight line from an incoming government's policy proposals to certain types of companies that will benefit.

"When President Biden took office, everyone thought he was gonna be great for green energy and terrible for dirty, old crude," he says. "Well, take a wild guess. Energy is the best performing sector under Biden."

Meanwhile, during the duration of President Donald Trump's first term, energy stocks were stagnant. That defied the logic that a "drill, baby, drill" president would be a boon for the oil industry.

Trying to pick winners is "tricky for a lot of investors who think this is easy," Detrick says. "There's never an easy answer. It's usually harder to find."

Picking future winners is 'a difficult game to play'

If you're hoping to glean information about the market based on policymakers' plans, you're looking in the wrong section of the newspaper, says Detrick. "It's not worth getting mixed up in policy," he says.

Instead, he suggests, "follow the economy. Follow what the Fed is up to. Follow trends in inflation and interest rates. That's going to matter a lot more for investors."

In the long run, stocks don't usually move based on what the President or Congress does. They move based on fundamentals, such as corporate earnings and debt levels, and in response to what's happening in the broader economy.

Remember: Investing is a long game. You're looking to build compounding returns over the course of decades. While you could potentially juice your results if you make a savvy move over the short term, chances are, you could still do better, long-term, with a diversified, broad-market approach.

After all, even most professional investors don't get it right. Consider active mutual fund and exchange traded fund managers who go into the office every day to create a portfolio that will outperform their benchmark index. Over the decade ended in June 2024, just 29% of their funds survived and beat their average peer that just followed an index, according to Morningstar.

None of which is to say that you won't be clear winners and losers in the market under the new regime. It's just rarely a good idea to try to anticipate them in your long-term portfolio, says Detrick. "There may be some near term worry or excitement about potential policy, but big picture, that's a difficult game to play."

Correction: This chart has been updated to include the correct start and end dates for the Trump and Biden administrations.

Want to make extra money outside of your day job? Sign up for CNBC's online course How to Earn Passive Income Online to learn about common passive income streams, tips to get started and real-life success stories.

Plus, sign up for CNBC Make It's newsletter to get tips and tricks for success at work, with money and in life.