Johnny Manziel may have the most variable draft stock of all quarterbacks heading into the draft. Some project that he’ll be snagged in the top five while others think he’ll be sliding down the draft order Brady Quinn style. There’s no denying his playmaking abilities, but what could scare teams away from pulling the trigger on Manziel?

First off, Manziel’s height is a concern. Russell Wilson may have done wonders in breaking the misconception that short quarterbacks can’t get it done at the pro level, but Wilson’s meteoric rise has to be viewed more as an exception to the rule in regard to young quarterback development. Wilson proved that short quarterbacks can be effective, but height, or lack thereof, still makes the job more difficult.

More importantly than Manziel’s height is his style. There’s a lot of debate about how that style will translate to the NFL. The problem, at least in some general managers’ minds, is that quarterbacks have to be top tier passers to sustain success over the long haul. After all, the two most prolific quarterbacks over the last decade, Peyton Manning and Tom Brady, are both pocket passers with little mobility.

Manziel’s ability to improvise will almost certainly bail his future team out of a number of close games, but it’s equally likely that he’ll cost his team games as well. It’s a similar trade off that the Steelers have with Ben Roethlisberger. He makes extraordinary plays outside the pocket, but at times he makes big mistakes trying to extend plays.

It’s because of his unpredictability that opinions of Manziel vary so wildly. Manziel is a quarterback that will almost always try to make a play instead of cutting his losses. It’s unclear exactly how he’ll adjust in the NFL, and that uncertainty will probably keep him out of the top five on draft day. GM’s know that they need a top quarterback to win, but taking a quarterback in the first round is a dangerous proposition with a bust potentially sinking a franchise for years to come.

There’s nothing inherently wrong with Johnny Manziel’s style, but there’s too many unknown factors to justify a top five, or even top ten, selection. Early in the draft, there’s nothing worse than taking a player you’re not sure about. There’s no safe picks, but there are picks that are safer than others, and Manziel is not one of those picks. So unless there’s a team completely in love with the idea of bringing in Manziel, don’t expect him to fly off the board quite as early as many analysts think.