What is a catch?

[Tomkat]

(01-23-2023, 01:23 PM)Isaac Curtis: The Real #85 Wrote: You were missing the replay and have the rule wrong. It is not like breaking the plane. 

Yea, the first replay I saw was from the other side... couldn't see the ball through Chase's back.  That's the replay where I saw "3 feet-steps."
THIS angle shows the ball move when the defender swats at it.  Now I understand why it was ruled incomplete.