Me: "I've got this repo on Github with millions of downloads and 10k stars. It's at least 20k lines of my own code. Would that be good to demonstrate my coding ability?"
Them: "Haha, no, that'd be too much work for us. Please do the test instead."
Me: "Fine."
Then they rejected me because I used GET instead of POST. Clearly that shows I have no idea how to code.
That was a large (1000+ employee) YC company, by the way.