Most people focus on short-term history and are biased by it. We are constantly re-fighting the last battle while failing to realize the current battle is probably completely different and what worked in hindsight may be disastrous going forward. I hear lots of youngsters jumping up and down saying they wish they could relive 2008 or 2011 and invest more. The next drop won't be the same and nobody knows quite how it will be different. There have been *10 year periods* of net negative Dow performance. You may be investing in one the next one. What goes down must come up, but it may come up too late for you to maintain your ER plans.