can someone explain the difference between soft tips, mid tips, and stiff tips.

I believe my ball is blocking right because i have a soft tip shaft
(club is lagging behind the swing). I am hitting the ball on the center of the head.

I think i need a stiffer tip....I am going to go to a club fitter to get fitted but like to know what is going on in the processes. Can someone help me understand this plus the benifits and negatives
ed