[CharlieDigital]

    > But then when I launch, I either don’t get much feedback at all, or I get a lot of feedback for a day, which then dies down completely after the launch.
    
    The harsh reality is that most products fail and due to so many failed attempts, I kind of internalised that I’m doing effort for nothing.
    
    But then whenever there’s a sale or a positive comment, I get another small jolt of motivation and I can build a bit again.

I'm the same way as OP, but I think this is easier to overcome if you build things that are useful for you or someone you know. Unless you're going to slog through tons of user interviews to properly validate your ideas, then just build it for yourself; build for fun and curiosity.

There's nothing wrong with that.

Despite Garry Tan's advice, I ended up building a travel planning app (initially just for personal use). I shared it with Reddit and ended up with a few thousand users. It had a big peak of active users that's settled down into a small community of very sticky users; never a commercial success. What keeps me coming back to it time and again is that I use it myself to plan my trips and every time I take it on a trip, I learn something new and spend a bit more time tidying it up or adding some missing feature.

[JusticeJuice]

I just looked up your app out of curiosity, and realized I had just watched your video about react's inverted-reactivity model just a few hours ago! Small world!

[CharlieDigital]

Small world, indeed! Hope that video was useful/interesting!