There's a massive market for one-off custom Windows apps fulfilled by short term contractors and consultancy firms or in-house programmers. It's a thing. Also

There's a massive market for one-off custom Windows apps fulfilled by short term contractors and consultancy firms or in-house programmers. It's a thing. Also, most software is deficient in some way. Software is hard. Edit - also Linux hasn't really been the market for apps like that (not saying there's not shitty apps written for Linux though). There is now a janky app market for iOS (tablets) and Android as well though. I've seen lots of custom tablet apps for small businesses that are complete shit. It's not just Windows, Windows just happens to be the de-facto enterprise OS and thus attracts that scene.