Basic whiteboard interviews and algorithmic questions, combined with a glacially slow recruiting process, being moved between many recruiters, and knowing that no real interest is kept in you.

Interviewers have no choice in being interviewers, so many of them would literally rather be doing anything than being in the interview room with you. One of my interviewers hardly spoke to me except to mildly insult me during the course of a question.

Find a local minimum in a list.

Implement the Game of Life.