- They are aimed at identifying smart people who know the basics of coding and algorithms. They are intentionally not domain specific. In my experience, smart people can pick up all the other details over time. I've worked with many people who switched languages and within a few months were (for the purposes of their job) as good as someone with years of experience. Similarly, version control, testing etc. are things you can learn on the job.
- They have worked for major companies. Look at the share price of Google and Facebook over time, or the general feeling that they are successful in their goal of hiring the best people.
- They are fast and scalable. They only take as long as the interview, and they scale well because it's easy to compare the notes of different interviewers. The process takes about 5 hours for the interviewee, and about 10 hours combined for the interviewers.