It is difficult to know when you 'have enough' money because like death, you never know what is around the corner. Most of us earn, save, and spend money during our working lives so that we can retire comfortably; but it seems like there is no magic number for when we have arrived.
How long will we live? What will our health be like? Would we like to travel? Leave the kids an inheritance? Give it away? All of these can influence the number.
The secret to amassing wealth is to always live beneath your means; but don't forget to enjoy yourself as you make the journey towards retirement.
Lots of people enjoy what they do. There's no reason any of the billionares HN complains about couldn't go retire but they don't. Most of them are busy AF. Because they want to be as clearly they have the funds to stop