Every gamer knows that moment of pure joy discovering a fantastic indie game, only to have it crushed when you realize you can't remap those damn mouse buttons. You're stuck with the developer's bizarre idea that M4/M5 should trigger self-destruct or open your inventory when you just want them for weapon switching.
Ten years of software engineering experience and I still can't fathom why key rebinding is treated like some exotic luxury feature. It's literally a hashmap, people. A HASHMAP.