What was the major flaw in the stanford prison experiment?

Question: What was the major flaw in the stanford prison experiment?

The main purpose was to understand the development of norms and the effects of roles, labels, and social expectations in a simulated prison environment. Main flaw in the experiment is The study has received many ethical criticisms, including lack of fully informed consent by participants as Zimbardo himself did not know what would happen in the experiment (it was unpredictable). Also, the prisoners did not consent to being ‘arrested’ at home.