It seems kind of obvious now, but building and working on something that scratches my own itch is an absolute game changer.
I've worked for companies that built software that wasn't used internally. I've also built apps in where I wasn't included in it's main demographic.
Now at the time, I felt like I was giving my all to those projects. But every once in awhile ( other developers will know what I'm talking about ) I would get these complaints about how the software ran a tad slow, or how a button doesn't really make sense where it's located and should be moved two inches to the left, or how the hierarchy of pages or screens seems a bit backwards.
Here's where the problems arise. As the builder/creator of the product, it's easy to chalk these complaints as nothing more than... complaints. Does it really make sense to make these changes? "It's most likely user error" is a pretty popular saying I hear and say.
Plus, what's the cost/time of making these changes? Does several days of development time really make sense to rewrite HTML to move the button two inches? ( Idk for whatever the reason moving that button destroys the layout of the rest of the page, It happens )
The point is, there is a conflict of interest there. The user just wants the app to be easy to use. The creators/builders have to outweigh the resources used to make or build the change to make the app easier to use, even though the creators/builders aren't even fully convinced that the change will actually accomplish that because they don't use the product!
But... if the builders and users are one in the same... the conflict of interest essentially disappears. You'll know if these complaints are justified because you'll experience them as well! And if they are justified, you'll make the changes because you want to be able use it with ease! You'll do it for yourself if anything.
Scratch your own itch, because we're all selfish. And what's good for you, becomes what's best for the product, which is what's best for the users, which benefits.... You.