"Work on your Zarrow"

Why is it that whenever someone posts a video with a zarrow someone always comments with "work on your Zarrow"?

Let's face it, anyone that can do a zarrow can spot one. It's not a move that can be performed without a single tell. The only way to hide it is to totally cover it- which is just as bad.

Every magician wants to think he is exceptional at what he does. By telling someone to "work on your zarrow" they are just trying to let everyone know that they could see the move. Let's give good zarrows their due credit people.