Are you suffering from decision fatigue? Do you have better things to do than oversee a complex portfolio and keep up with the latest on Wall Street? Do you just want to do as little as possible when it comes to investing but still have the money you need to meet your goals?

If so, good news: Your exhaustion and disinterest might make you a successful investor if you adopt a portfolio strategy we’ll call KISS (Keep It Simple and Smart).

The key to the KISS strategy is to not waste effort trying to select the “best” of anything – stock funds, managers, complicated sector plays. And, instead, to feel confident you can do well enough for your individual goals by sticking with a few low-cost funds over time that track overall market performance.

Why? Because, it turns out, “It’s extremely difficult to beat the market,” said Amy Arnott, a portfolio strategist for Morningstar.

Indeed, data from Morningstar suggest most actively managed funds don’t.

Researchers compared their performance after fees to a composite of passively managed index funds and exchange-traded funds.

“Just 21% of active strategies survived and beat their passive counterparts over the 10 years through June 2025,” they wrote in a mid-year report about Morningstar’s Active/Passive Barometer.

As just one example of how actively managed funds may disappoint, Morningstar found that over 20 years, only 7.1% of large cap blend funds – which invest in both growth and value stocks and might compare their performance to the S&P 500 – performed better than index funds in the same category.

If the bulk of your money is in a workplace retirement plan like a 401(k), chances are you will have the option to invest in a target-date retirement fund.

Such a fund allocates your money across other stock and bond funds – often index funds – to achieve an allocation that best suits your time horizon to retirement. So for someone who’s 40 they might be in a 2050 or 2055 target date fund.

The fund’s allocation will grow more conservative (less in stocks, more in bonds) as you near your expected retirement year.

“A target date fund can be a great option. It builds in portfolio diversification and an asset mix targeted to your age and retirement date,” Arnott said.

If you don’t have a target date fund, or don’t like the one available in your plan, consider investing instead in three broad index funds and adjust how much you invest in each according to your risk tolerance and time horizon.

“The average person probably will get better results with a target-date fund. But if you want a slightly more hands-on approach you could put together a basic portfolio of US and international stocks plus investment-grade bonds. Having exposure to those three asset classes is all you really need,” she said.

Beyond retirement, for any investing you’re doing to meet intermediate-term goals with a five- to 10-year horizon, she suggests putting money into a high-quality intermediate-term bond index fund or a low-cost, actively managed one, since this is one arena in which actives have had a reasonably good track record against their benchmarks. Or you might also consider a low-cost, moderate-risk allocation fund of funds – which invests in both stocks and bonds.

Just as having fewer but better clothes in an organized closet can reduce your decision fatigue about what to wear, adopting a KISS strategy with just one or a few, low-cost funds can reduce the stress of managing your investments.

With a simple, streamlined portfolio, you’ll know what you’re invested in.

It will be easier to review – which you should do once a year to make sure the way your money is allocated still reflects your risk tolerance and time horizon.

And your portfolio will be easier to explain to a spouse or adult child, who may help you manage it if you become unable to do so alone, or who will eventually inherit it.

“As I’ve gotten older and my financial situation has gotten more complicated, I’ve come to appreciate the value of simplicity more,” Arnott said. “There’s a lot of value in having a portfolio that is easier for someone to take over when you’re gone. Or if you’re an older adult with a cognitive impairment.”

And, perhaps most importantly, having a simpler portfolio may make it easier to assess whether you need to save more now. Because no matter how well your investments do, if you aren’t saving sufficiently, the best returns in the world won’t get you where you need to go.