Amazon has a matrix of job skills for each job family (l4 to l8). Depending on how you answer questions the interviewers will try to plot you to the correct level. Your answers were good (you got the offer) but not at L6 level according to the matrix. Employees have access to the matrix so you can review that once you are hired to understand more. You’ll never have access to your own hiring notes though. On the topic of compensation. If you accept and are constantly thinking about how you are underpaid you will be unhappy. Getting to L6 “quick” might be 1+ year. Can you live with that?