This and the details about the process in
https://blog.usejournal.com/rethinking-how-we-interview-in-microsofts-developer-division-8f404cfd075a
really give a good idea why this price works so well, especially for candidates:
you get the opportunity to really show the way you think and approach new
problems, which is in the end what we hire engineers for!
https://twitter.com/mjackson/status/1079502682807664640