Mike Sando's 2015 QB Tier Rankings, in which he polled 35 NFL insiders for their opinions on the league's 32 starting quarterbacks, had the Oakland Raiders' Derek Carr tied for 20th overall. That was on par with Jay Cutler and ahead of Nick Foles and Sam Bradford. On the surface, it's easy to understand the optimism surrounding Carr as he enters his second season. After a slow start, he led the Raiders to three wins in their last six games. Perhaps more importantly, he seemed to show up biggest in the most important moments: His red zone performance was the best in the NFL, according to Football Outsiders metrics; his Total QBR was at its highest in the fourth quarter; and his 21/12 TD/INT ratio was better than Andrew Luck's rookie-year mark (23/18) three years ago.

So what's not to like? Carr appears to be a cautionary tale about focusing on the wrong numbers. While Carr and Luck posted almost identical rookie years by traditional passer rating (Carr 76.6, Luck 76.5), their QBRs were quite different (Carr 38.4, Luck 65.2). And forget about Carr getting better as the season progressed: During the Raiders' 3-3 stretch to end the season, he posted a minus-16.6 percent mark in Football Outsiders' defense-adjusted value over average (DVOA) metric (explained further here). That was worse than his performance during the Raiders' 0-10 start to the year (-13.8 percent).

Using the right numbers, it's clear the odds are against Carr becoming a middle-of-the-pack quarterback.

Rookie seasons are telling

There have been 18 quarterbacks drafted outside the top 10 since 2000 who threw at least 200 passes as rookies. Carr ranks ninth in this group -- right in the middle -- according to DVOA. That sounds promising until you realize that most quarterbacks drafted outside of the top 10 fail in the NFL. The ones who have succeeded were generally pretty good as rookies.