Get us to a Super Bowl and win it.
That's how he's going to be judged.
He's the quarterback of the Dallas Cowboys. And the standard is Super Bowl victory/victories.
You can tell the differences in generations: the Cowboys fans who lived through the glory years of the 70s and 90s generally (not all) hold Super Bowl titles as the standard for Cowboys quarterbacks. Those born after the Cowboys' heyday and those accustomed to playoff futility generally (not all) offer NFL stats (fewest interceptions thrown over a four year period, winning record, 400 plus passing yards, etc.) as the standard.
My, my, my. How far have our expectations as fans fallen.