I went through a multi-stage interview process: multiple recruiter calls, a meeting with the hiring manager, a meeting with a senior manager, and a final writing assignment after being told it was down to me and one other candidate. Two days after submitting the writing sample, I received a generic automated rejection email... no feedback, no direct communication, no closure. I even followed up directly with the recruiter after that to get anything at all, but nothing.
I thought the interviews themselves were positive, but the way the process ended was completely unprofessional. If a company takes candidates through that many steps, the minimum courtesy is a personal follow-up.
Oh and two weeks later, I see the job posting up on LinkedIn again.