My current employer already has a problem getting otherwise bright & capable candidates to submit code samples against a simple problem that take experienced devs all of a couple of hours to do. They decide the hurdles to hire elsewhere are lower, and don't bother to finish our problem. Yeah, you might say maybe we don't want them, but the truth is that sometimes we do, and it takes a very long time to fill some of our positions since top talent has their pick of jobs. The core issue is that they don't generally know us as a company before the hire process begins, and therefore have no personal incentive to prefer us ahead of time. We aren't Google, we don't have Google's reputation, and we aren't going to become Google anytime soon.