Amazon Manager - Operations interview questions

After applying online I was contacted with a day to setup a phone interview. Phone interview was very informational and pleasant. The position was first described in greater detail, behavior based questions were asked and the opportunity to ask questions was given before closing the interview.

I only attended 2 rounds , out of the overall 4 rounds. The first round was Process or operations round and the second round was HR Operations round was good and all questions were related to know your process knowledge along with some analytical questions were asked like if you have 9 balls and one is lighter one how would you identify the lightest I cleared this interview second round was HR and it was good and relevant to the role however I could not clear it