People tend to keep bringing back the narrative about a person who missed the ten biggest gaining days and how missing those days could destroy your lifetime return.
First, the obvious, this is disingenuous as they cherry-pick big gaining days and assume you hit the biggest losing days.
But it is far worse than that. The two are highly correlated and they all occur in major market corrections. If you look at the following link you will notice that this is true for all of the top 20 gaining days. Almost all were in the middle of the Great Depression or Great Recession. The others were this week and the Covid crash and recovery.
https://en.m.wikipedia.org/wiki/List_of_largest_daily_changes_in_the_S%26P_500_Index
If you tried to make the worst moves possible, it would be statistically impossible to hit the bad days and miss the good days.