The only way to set hourly reminders is to divide from 24. Other apps have hourly categories, thus, more well-designed interfaces.
Some devs get feedback and nimbly adapt to improve their apps. Some devs convince themselves that it's end users who need to adapt. By that reasoning, why bother with graphical user interfaces at all when you can get it done with flow charts and logic boards? This developer is of the "blame the end users, my app's perfect" crowd. The efficieciency of markets will drive consumers to responsive developers who make the apps consumers want.