In school we learned that initial velocity is zero for dropped objects, but why?
I'll tell what, let's head over to the pool and I want you to stand on the diving board.
Well, are you moving?
Now jump in.
Now stand on the diving board.
When you were standing on the diving board you were at rest, which is why your initial velocity was zero. Then, when you dropped into the pool you accelerated which resulted in your change of velocity.