Earlier quoted context omitted.
And this imaginary "Bob" still lost a ton of potential gains and psychological trauma because of his poor timing. He did not come ahead of the 90% of investors, he was in the 90%. Investing blindly in any market is a terrible idea and ignorant advice. Buying and holding is a terrible strategy, especially during crashes or leads up to crashes. "Bob" invested at the peaks of four market cycles and suffered heavy losses…
The >90% don't invest at all and end up worse than Bob. Bob isn't real because it requires perfect market timing and yet even if you were as unlucky as Bob you'd come out ahead. That's the point, that you don't need to worry about timing if you just invest consistently. Calling other people ignorant when you're trying to peddle market timing as a strategy is a bold move...
If you're an American, the number isn't 10%. 32% of Americans have a 401k. So 32% are investing and a solid portion let their 401k management bank make decisions for them/go by the typical advice given, by bank reps, of "aggressive portfolio when you're young" (majority stocks), "moderate when you reach middle age" (mix of stocks and treasury bonds), "conservative when you're older" (mostly treasury bonds).
If you're younger and signs are pointing to the market crashing within a year or two, your management bank is going to advise on this and tell investors to move their money to cash (if there's even a cash option) or to treasury bonds. No, it's up to the investor to make a decision based on their own research/reading of the signs. Hell, these banks even use dark patterns to make it more difficult for investors to manually control their own portfolio, leading to users giving up on finding or thinking that they can't manage their portfolio and leave it up to the banks to do so.
There are signs for when things aren't going so well and things are going to take a turn for the worst soon. Certain indicators can help with gauging this. No where near being 100% accurate, maybe 52% accurate, but that's still an edge. On top of certain indicators, monitoring quarterly GDP, yield curve rates, unemployment rates, home owners rates, among other stats, help to show what lies ahead. If one can get out some months before a crash, then great, it's likely that they didn't get out at the peak of the market cycle, but at least they likely saved their 401k from a 20% drop. And in the case that they did move to a cash option at the peak, then they likely saved themselves from a loss of between 40%-60%. If cash isn't an option, then likely saved around a 35-40% loss.
Investing blindly isn't a good strategy no matter how one looks at it, but learning what to look and monitoring periodically can help in preventing catastrophic losses