I agree completely. The other point I guess is that if you build something that satisfies a need for you, you're far more likely to use it day in day out. Using

I agree completely. The other point I guess is that if you build something that satisfies a need for you, you're far more likely to use it day in day out. Using your own product is extremely valuable, and it's surprising when you hear of businesses that don't use their own products - how will they know what needs fixing/improving etc. And making something you want means you likely have a lot of knowledge already about the space. It's like an author being told "Write about your own experiences - write about what you know". Also it really surprises me if someone is working at a big company 9-5, and doesn't have a side project. Get a side project all you people! It could turn into something other people want as well.