Interviewing is a random event for many companies. You as a candidate could fail miserably on one day and get great feedback the other day. It depends on so many factors in larger companies. For example in one of my previous employers, they would send a random engineer (juniors included) to interview a candidate and give a mark from 1-10. There were engineers who would not pass their own interview and questions, and on the other hand, there were others who would just see that you can code anything and you are cool to work with and would let you in. And anything in between. There were times where juniors wanted to be smart and asked some puzzles they got from the net, and when later I asked them to solve them they failed. So many interviews depend on so many random events and circumstances and.

The biggest takeaway I got from all this experience is that as a candidate I should not be intimidated by anything and should just be cool and myself, because there is so much randomness that trying to find reason in it will just make things worse. And ALWAYS negotiate as much as you can because your biggest raise is when you get hired.