You're forgetting the fundamental rule of the stock market.
Buy low, Sell high.
Buy low, Sell high.
The people that got in in 2008 made out like bandits. The people that wait until 2010 or later missed out on a lot of the gains.
If you look at June 2007 to Feb 2020 (missing the current dip), the return is 8.75%.
Come up with a good definition of "low" and "high" when you don't know the short/medium term future, and you'll have figured out this whole "investing" thing better than anyone else!