They gave me a problem-solving question about how I would approach a machine learning problem in a manufacturing context, focusing more on my thinking and overall approach than on getting the exact right answer.

I applied to this position and went through 4 stages of process: 1-Coderbyte coding assignment/exam. There were 4 questions, 1 hour time. 3 problems were easy/medium. Last one was hard. But exam is easily doable. 2-Interview with HR. Asked about motivation. 3-Technical interview about applied physics and ML, and computational geometry. Pretty awkward interview. The interviewer was trying to show that his approach to the solve question was better than mine, which may be true because he designed the questions anyway. And he was not able to answer a basic question I asked at the end of interview about their models and their reliability and validity. 4-Technical interview about a coding problem. Nice interviewer. The problem was from an ICPC contest. I was able to provide a valid solution, and then I was asked to implement my solution in python in a live coding setup in the same interview. I implemented my solution and my code successfully passed their test cases. After this last interview, my application was rejected with a pretty generic rejection message. And tbh, I don't care because I have offers from other companies and wasn't going to accept offer from NC unless the salary was well above market average, But it's weird to see getting the rejection email after a successful interview.