You stay up late the night before, preparing a presentation for that class you hate.
Everyone has to present. Everyone was assigned one section of a rather specific topic, and was told that they would be presenting on that specific day.
So the day comes and all your classmates quietly meander in, as if reciting the material to themselves.
Then the teacher comes in and starts the class.
You exchange a glance to the classmate to your left. What about the presentation?
The person to your right catches your eye. Did I read the homework sheet wrong? Were we not supposed to present today?
Eyes wander the room and relieved grins are held. Everyone almost telepathically nods at each other, thinking in unison with each other, you say nothing, I say nothing, we will all say nothing.
And thus, the presentation deadline has been extended.