Ververica interview questions

I had to go through FIVE STAGES (with number 5 STAGES) in almosty THREE MONTHS of the process, and all cleared. Later on I was given assurance about my candidacy, I was just waiting to receive an offer since I had passed FIVE STAGES of interview rounds. And boom, I received information that I was not selected after FIVE STAGES of interviews. Huge disappointment since I had a very nice talk with the engineers however this company seems to not care about candidate's time and effort. That's also why they have very negative candidate feedbacks for interviews here. Be careful to not waste your time with them, it is huge disrespect to the candidate who has received fully positive feedbacks from literally everyone in the company, but then they ghosted me for 2 weeks and came back with negative result which was shocking.