Solo devs who ship consumer apps, what's the part of running the business that surprised you most?

Not asking to be answered, mostly want to hear other people's version of this. I make SpeakUp (getspeakup.app), disclosure, a Mac dictation app, one person building and running it. The part that surprised me wasn't the coding, that's the part I was actually prepared for. It was how much of the week ends up going to things adjacent to the product, refunds, a support email that turns into a half hour back and forth, writing about the thing instead of building it. None of that shows up when you're planning the build. The other one, nobody warns you how much slower organic growth is without any ad spend. Every new user right now comes from somewhere I can trace, a Reddit thread, a forum post, word of mouth. No amount of code fixes that, it's just a different kind of work.

For other solo builders here, what's the thing about actually running it that you didn't see coming when you were still just building it?