For one thing, Zach often bails out of the pocket when there's no need to bail out of the pocket.
Second, it seems like the greats move around in the pocket when there's danger. Seldom do I see them turn their back on the play even when there's a need to escape and prolong a play. The way Zach does it is way too predictable. You know what he's going to do.
Again I'm no QB expert. I just like to watch football.