And might even be fun to implement and maintain.

I think we have a winner. This sort of personal toolsmithing is fun, and you can try out some new programming language or whatever.

We all love a good excuse to build something small-to-medium sized for our own perfect "tailor fit" preferences.

All the excuses about other tools not being adequate are just what we need to say to ourselves to justify the time ;)

This starts to sound like something someone might waste time building instead of actually being productive…

In terms of earning money, but surely that's not what's it's all about, is it?

Does everything you build must be useful? What if it's just really fun?

If the tool brings you (you, as in: the one building it) joy and gives you a chance to let your mind float, then yes, it is useful. Just not for others. And that's fine.

Define useful and who it has to be useful to? If building it helps me improve my craft, let's me decompress and have so fun. That's useful

Exactly. Most people wish they could customize their Todo app or system to their specific preference or need, but have no way of making it happen. Devs can, so they do.

What's interesting is AI is going to change this. Entering a prompt for an app that has all the features you want is already pretty trivial, and will only get better.

Which is why everyone likes spreadsheets. You learn a few formula and styling rules, and you’ve got a hammer for every nail that’s been bothering you (if it was actually a screw…shrugs).