AWS pentesting is an extensive process that requires a wide variety of knowledge and dedication, and it really is a never-ending process. There are always new services and functionality being released by AWS, so there will always be new security checks and attacks for those services.
As a pentester, it is difficult to be able to say you are done pentesting an AWS environment because of how massive and complicated they can be, so it is important to hit as many different services and attacks as possible, all while staying within the timeline that you agreed upon with your client.
Every real-world pentest that you do will likely vary greatly from the previous one. With the size and complexity of AWS and its offerings, people will be doing things differently wherever you go, so it is important to never get comfortable and instead always expect to be learning, teaching, and...