People don’t actually track wall clock time, I’ve noticed.

at which point you realize you never had a plan written down and you are using the code as a spec

But have you thought about “fun factor”? It’s where you sit like an addict in a casino for weeks and burn tokens in a hope of winning a software that you could’ve written? Who doesn’t consider “fun” thinking about work crap all the time, writing to your agent, verifying walls of slop?