I recently sent an email to the professor, who accepted me to carry out my postdoctoral research in his group. However, I wrote him an email to ask quick but important questions, like, when do you want me to start. I didn't get an answer even after a week. And similar things happened before as well.

So I want to ask that as a professor, sometimes will you (on purpose) to NOT answer emails in time?

I recently joined a research group as a postdoc. I wrote the professor an email to ask quick but important questions including asking him when when he wanted me to start. It's been over a week and I haven't received get an answer. Other emails I've sent previously have also gone unanswered for long periods as well.

With that background, my question is: do professors sometimes (intentionally or otherwise) not respond to emails in a timely manner?