This flows from Creation can be Selfish.
personal software is not guaranteed to fit to a purpose. it doesn't have to be something that someone else can pick up and expect to use freely.
things can be broken out in components that can be shared more liberally, and held to higher standards, eventually generalized to other use cases. this is a healthy lifecycle for software which supports communities and communities which support software. It doesn't have to be a product, it doesn't have to be productive, it doesn't have to be profitable.
personal projects are spaces to experiment and learn
my personal projects, and the ones which feel most rewarding, are personal tools. software designed to fit a need i have. for me.
personal projects can have scale in the hundreds of users, and can necessarily be less if you want them to be. my tools can use ineffecient reporting code, because only one user will be making reports. i can use unproven technology and invent design patterns that don't make sense when working on software with other people