I retired a few years ago, shortly after I turned forty. I worked in Silicon Valley for a long time and saved almost all of my take-home income, which is what allowed me to amass a large sum.
When I was living in Silicon Valley, I couldn't wrap my head around how much pointless consumption my colleagues engaged in. Couldn't they see that they could escape this stupid rat race and leave if they just saved their money? I guess the liked the rat race more than I did. I hated the rat race and don't regret leaving. I should have retired sooner.