I went through 2008 and learned. I worked some extra years (I’m 64 now) just so I had some cushion. I didn’t want to be losing sleep at night over the economy.
Waiting too long can be a real issue as well. I know many who couldn’t pull the trigger and then couldn’t do what they had planned on during retirement due to health issues. That’s where the financial advisor helped me. They told me years ago I could make the leap any time, after going into significant detail into what we expected out of retirement. Those last few years were great because I knew I could quit any time I chose. The pressure was gone. When I quit, we made the decision over one weekend because we had done the planning over the years.