The Vanguard S&P 500 ETF (VOO) is the largest ETF on the U.S. market, with just over $1 trillion in assets under management. It got there because of several compounding factors: the strong performance of its underlying benchmark, the S&P 500 index, Vanguard’s brand reputation and economies of scale, an ultra-low 0.03% expense ratio, and, frankly, some catchy investing slogans.

One of the most popular is “VOO and chill.” The idea is simple. Put your money into a low-cost S&P 500 index fund like VOO, stop tinkering, and let time do the work. Like a lot of things you see on social media, it sounds good in theory.  In practice, though, your mileage may vary.

I want to be clear upfront. As shallow and elementary as…