Here's a question to play with. Pure speculation, but why not. In Luke 1, when Zacharias questions Gabriel, the angel gets miffed and strikes him mute. He'll stay that way until John is born.

Further on, the same angel gives his message to Mary. Mary questions him, and Gabriel patiently explains the answer.

If he didn't like humans questioning him, why didn't he punish Mary the way he did Zacharias?