I just had my onsite interview for Meta and I found it really strange that my interviewer only asked me behavioral questions for 30 mins. I used the STAR approach when describing my projects and experiences and I couldn't catch any red flags when talking about my experiences, so I'm surprised that it only lasted for 30 mins and I'm a little worried as to why it was so short. I cross referenced my answers with the junior level interview performance and it matches up with what Alex described. I did fill the remaining 15 mins with questions based on what Alex suggested. Does anyone have any thoughts?
lol. So one of my friends had a similar interview experience when he did his onsite at Amazon. It was two questions and they just chatted the rest of the time. He got an offer and ended up being a really high performer at Amazon.
But back to your situation. The question behind your initial question is whether your super short onsite is a sign you failed the interview.
You're overthinking after the interview. You already did everything you possibly could do. They could have put you through a grueling interview loop if they wanted to. If they wanted to, they would.
TLDR; you're overthinking, just wait it out.
There's not enough depth in a junior engineer's experience to be able to have a thorough behavioral interview.
By the time I become an approved interviewer at Meta, the direction of E3 hiring had already heavily shifted towards hiring returning interns, using them to fill 80%+ of E3 headcount. Because of this, I was on very, very few E3 loops (as there aren't many to begin), and of the few I was on, I don't really remember them 😅. In particular, I don't remember if E3 behavioral rounds are supposed to be shorter according to protocol as there's really not much depth you can extract from a junior engineer in a behavioral round.
Anyways, here's what I do remember about how E3s could fail a behavioral:
If you had decent charisma, eloquence of communication, and answers/questions matching what I go through in the course, you should be fine for this round.