Analytical food for thought on the disparate QB situation in the NFL over the past 10 years…
Top-10 Uniqueness
36 different QBs have been in the top 10 (as ranked by NFL.com) for the last 10 years, with a total of 100 combined top 10 years collectively. Therefore, there is only a 36% uniqueness by person of QBs of the Top-10 QB spots (of what could have been). If there have only been 36 different Quarterbacks to crack the illustrious NFL Top-10 list, and more than 187 different QBs to play in the same time period, then every QB (all things being equal) had about a 1-in-5 chance of making the Top-10. Not bad odds at all, considering the probability of playing at the NFL level coming from High School is only 0.2%.
Probability of a Top-10 / Elite QB on Your Team
We already examined the probability of any random quarterback being a Top-10 player, but what about your team landing one? If there were 320 possible team-years (32 teams x 10 years), and only 36 players were Top-10, that means teams only had a 11.25% chance of having a top QB on their squad on any given year in the last 10. The overwhelming majority of teams (88.75%) did not have an Top-10 QB any year. If we consider those QBs that got on the list one time as “good QBs” (instead of elite), that leaves us with only 20 elite QBs, or a 6.25% chance of your team having a Top QB in one of the last 10 years. (And I would argue you would need to bump that number up to at least 4 years on the last – Jay Cutler, Jon Kitna, Chad Pennington were/are not elite…doing so drops the probability all the way down to 3.44%). If we can assume for a minute that Peyton Manning, Drew Brees, and Tom Brady all were on the same team for the last 10 years (I know this is not entirely true but makes this analysis much easier), that leaves us with 17 “elite” QBs divided by 290 team-years, or a 5.86% chance your team had an elite QB at some point. So what does this oversimplified analysis all mean? If having a top QB is a necessity (or at least strong indicator) to win games, and only 1 in every 20 starting QBs was a top QB (in the last 10 years), then your team will need to focus on something else to win games. This is also a good indicator of coaching strength, as teams that can win without top QBs have relatively strong coaches and teams that lose with top QBs are relatively weak.
Source: NFL.com Statistics