[zardeh]

You're exactly correct. Outside of 20% time, I can't see that example being really realistic (at least not at Google for an android launcher, there are other companies where I've heard of 10+ competing internal libraries for the same problem developed by different teams).

In the case that you're asked to implement a project from 'above', they're still useful, for practically the same set of reasons (maybe minus #5, but plus 'other people who you impact can provide feedback to reduce future friction')