I used to care much more. I used to try to help them. Try to make them feel good. But I can talk and talk, explain and explain, in the end we won’t hire you if you can’t reverse a linked list, or do a case-insensitive string comparison. I have done this so many times, I'm terribly frustrated about this. So now if you fuck up here, I’ll just let you talk for 20 minutes, say “uh huh” once in a while and review code in the meantime. And then I’ll ask you about “your most interesting project so far” or some bullshit like that.
Should probably read that to get an idea of the interviews perspective. They have to sit through tons of interviews with people who struggle with cs fundamentals.
They may start out initially being friendly and helpfull, but if they are in the hiring pipeline for too long, they will eventually become disinterested, because, as the throwaway from the google interviews explains : why give feedback, or explain concepts to interview candidates, it has probably reached a point where the interviewer knows you will not get hired, so they just switch off.