No one has trained these people in leadership skills, and it shows in the way that they perform their jobs (which is, all too often, very badly). Throwing temper tantrums via email is just one of the signs of an incompetent supervisor/manager, but even that arises from the fact that they haven't been doing their job properly in the first place.
A manager or supervisor who knows how to be a leader should never have the need to do such a thing. Why? Because the very definition of a competent leader is one who knows how to inspire their teams to perform well.
Ms. Supervisor/Manager: If you EVER need to throw a temper tantrum and if you EVER think that is how to bring out good performance in your people, you need to resign. You aren't fit for leadership.