First of all engineering graduates dont apply for this job they will reject you for no reason at all.
And the recruiter wont respond back to you for weeks and there will be no response for your mails and calls complete radio silence after the interview.
Why do you waste time of the candidates by nominating them to interviews if you are not interested/ afraid of their skills. Atleast be professional and send a rejection mail/call.
I did not expect this from amazon it is highly unprofessional to ghost the candidates after interview.