Apple

5 rounds over 3 days, high difficulty. Rejected due to a misunderstanding regarding my previous experience; they wanted someone with an electrical engineering background. Was recommended for another job instead, but declined that as well.

I applied through a recruiter. The process took 1 day. One day with 3 interviews, each one takes an hour, you have a break of 30 min between, nice interviewers, nice offices, they come back with an answer after a week (for no also).

Neutral environment. You might have more than three interviews in a single day, which can be pretty exhausting by the end of the day. You understand that if the hiring process is so hard, the job itself won't be easy as well.