I applied long time ago for some positions that I don't remember already. One day, an assistant of the hiring manager contacted me for an on-site interview (without any phone screen). I asked her what position I would be interviewed for and who the hiring manager is since I can't recall any positions that I ever applied for. On the scheduling part, they kept changing at last minutes, which is not very professional. As for the on-site interview, all interviewers (directors and managers) were nice and friendly except for the hiring manager. He was rude and picky about my technical background. He kept asking technical questions (sometimes non-relevant ones) to a point that other director stopped him. He never had eye contact with me and never mentioned himself as hiring manager, and left the room in the middle of the interview without notifying me first. Just left and was gone forever - no respect for people. I have a good impression for the company and its people except for this particular hiring manager.