You would like to be told why hours are extended when they are. Sounds reasonable. However, when you are asked to stay late by your boss and THEN you ask why, it will probably be taken as an insult. it implies that their judgement can’t be trusted at face value and needs to be questioned. I’d expect the boss to be defensive in such a situation. You have questioned his judgment and authority. Do this openly, in front of other coworkers, and I’d expect the boss to be even more defensive.

So what to do? Before you’re ever asked to stay late again, I’d go to them, in private, and explain that you’re happy to stay late and be a team player when the need arises. Explain that it makes you feel like your time isn’t being considered/valued when they don’t explain why you’re staying late. Explain that it might help morale if the do. Now it’s helpful and constructive, instead of judgemental. If done like this, before a request is made, I imagine your boss will be much less offended and defensive. I would be.

It reminds me of Jesus’s advice to us MATTHEW 18:15