One thing the time-based framework doesn’t account for is the mental energy you could save.

A small example: I sell a software product, and every now and then someone would ask for an invoice. So I’d have to look up the order, copy an ID and an email, make a PDF, and email it over. Was it hard? No, it took 2 minutes. But I loathed doing it.

So I wrote a little invoice page that looks up their order and let’s them put in whatever info they need, and generates a PDF. It took a day or two. I’m 99% sure this will never ever pay off in terms of time savings, but it gives me great joy to know that I will never have to do that energy-sapping task again.