bouncing ball

Bouncing ball is a basics for animation. Every one may be do this animation. Then get some important things "Timing and Spacings". I know this is a very basics but in here, I'd like to think a impact with bouncing ball.

Do you catch difference between left and right ball? 

The left ball has strong impact for jumping, but right one has strong impact for landing.

What makes this difference?  see the below.

left ball is landing and squashing is done on the same frame, but in the other, squashing and landing is done individually.  Which means we can see squash and landing not same time.
I don't want to say which one is wrong and which one is collect. Because answer is up to a shot.
In some shot we need landing impact but others we need jumping impact.
Just little differ makes lots impact for audience.