As a person who took part in interview process in FAANG and mid-size late startups (where some hiring process exists) it is not that they don't want to tell you. You usually have multiple interviewers that will score you on various dimensions. They would write their feedback which is then discussed on hiring commitee meeting by hiring manager and interviewers. If one interviewer think you didn't do a good job, this area would be scrutinized to see if other interviewers saw the same red flags or it was a fluke.
So to answer your question, recruiting coordinator needs to chase interviewer to write report before the commitee date and then decide if their feedback is bad enough. This is a no started because it makes no sense and coordinator is not qualified to make that call.
There were definitely cases where candidate did so bad, that process was cut short, so you were likely not in that bucket.
This is the answer. Yes, every interviewer will have to provide say whether they are inclined or not inclined for the hire, but the interview debrief is where the hiring decision is made, considering the total experience of all the interviewers.
Sometimes there is a candidate who is so obviously far from the bar that we could stop early, but if the phone screen process is working well it's rare. My experience is that the typical interview loop is ambiguous enough that it is rare that later interviews are a waste of time—these may turn out to be the ones where the candidate shines the most.
