Here a situation I want to ask you all:

You and your colleagues stayed back after office hours to work. You all are in the same team dealing some project. Say, you have finished your part (work/job/task), is it alright for you to leave first or you have to wait for everyone in your team to leave together? Btw, you are junior (just joined the company for 3-4 months). Is it a norm for you to stay back even if you have totally nothing to do so that other colleagues won't backstab/criticise you for leaving early?

I've been told by my friends that they have to stay back (even there's nothing to do) because their teammate/colleague/senior don't like the fact that they (my friends) finished early/faster than them OR even criticise their attitude for leaving the office early. I was like 'WTF........??!!'

So, I need to hear from opinions from you all.