Many successful people who've built and exited massive start-ups have suggested that it's worthwhile on the start-up side to spend 25% of your time on hiring when you're actually hiring as so you can easily get above 10 hrs a week given a full time role on this and have that be a good result. Optimizing to minimize the cost of hiring an early engineer is definitely solving the wrong problem, given the early engineers are almost as crucial to success as founders. Unfortunately, hit rate is also often the wrong variable from the company end: if you interview an academic programmer to confirm their product programming skills you generally get someone better with a larger skill set than if you focus in the category you want for the skills you want (early-stage you generally want breadth over depth for many roles). It clearly sucks for people on the receiving end of the low hit rate interview, but I'd caution start-ups against optimizing their process for the wrong things.