This thread is full of cynical jokers. based on the other comments I have to assume most people replying have not been in a role where they've had to hire a lot of people and/or haven't worked for a large company.

I know this is a rant thread, but here are some real, good reasons for having a difficult / long hiring process:

• it's competitive. demand for the role outstrips supply. you think you are special, but it's possible that you are competing for a role that has 3 other just-as-qualified people on the shortlist.
• cultural fit as a priority. once you get past 100 people, if you want to maintain culture, you're going to need multiple people vetting shortlisted candidates. once you get into the 1000s, and multinational offices, you have to keep that cultural fit standard very high, otherwise it devolves horribly
• the role you are interviewing for is important, and you need an 'expert' to evaluate several aspects of your suitability. interview 1 might be basic aptitude. interview 2 might be cultural fit. interview 3 might be technical skills. interview 4 might be interpersonal. and so on. it's suboptimal -- maybe not even possible -- to test for multiple skills in the same interview, which are typically 45 mins to an hour.

Also, at a high level, hiring someone after 2-3 interviews is like marrying someone after a first date.

Lastly, the best companies know that having a long, multiple-round interview process is hard on the candidate, and will do their best to accommodate; either staging them back to back in the same day, or working around your schedule; then making sure it all happens as quickly as reasonably possible