The interview process seemed properly structured. The HR took an initial screening exam (behavioral + technical) where I did quite good and was called onsite directly without any phone interviews. On the day of onsite, they took around 4 rounds of interviews with almost 50% technical and 50% behavioral questions.
The problem I found with the interview process is amazon customer support is too much obsessed and oriented towards amazon principles and fail to focus & predict on how the candidate would actually perform if given an offer. The behavioral questions based on Amazon principles that are asked during the interview are quite predictable and can be found anywhere on the internet, to which, anyone can do the research and prepare for the answers with situations that might not necessarily happened with them in past but just for the sake of clearing interview process.
My technical rounds were absolutely good and I answered pretty much everything so it is evident that they rejected me based on behavioral questions. I honestly find it silly and stupid because I previously worked at Cisco TAC for years where I performed quite good and was passionate to deal with customers. Their approach during the interview is 100% focused on if you can present examples that satisfy amazon principles. (I think this is stupid because anyone can browse over hundreds of blogs and prepare such examples just to assure them that they did good in the past and have wonderful customer managing/handling/pressure-handling experience.)
Overall, unlike Cisco TAC, Amazon's Cloud Support interview process was stupid and fails to identify actual skills the candidate possess. If you want to experience elite level technical customer support, I would rate Cisco TAC better than Amazon anytime (also based on the feedbacks I read online and heard from friends).