Bill Walsh said he needed two years to know Joe Montana would be the San Francisco 49ers' franchise quarterback. Walsh's coaching understudy, Mike Holmgren, generally thought the third year was when a starting quarterback should hit stride.

Waiting around for a prospect to develop into a franchise quarterback creates risks for decision-makers. Big bets made on Kevin Kolb, Christian Ponder, Blaine Gabbert, Mark Sanchez and others come to mind. Another wave of young starters -- Nick Foles, Cam Newton, Jake Locker, Ryan Tannehill, Andy Dalton, Matthew Stafford, Sam Bradford and Geno Smith among them -- carry the hopes of their franchises into the 2014 season.

Teams need answers sooner than later. What if how a quarterback plays right away tells an organization what it needs to know? Evidence collected over the past eight seasons supports that thinking almost without exception, providing a clear lens for viewing the game's most important position.

"The QBs who do well ultimately, do well as rookies or in their first season of starting -- they show you," ESPN analyst and six-time NFL executive of the year Bill Polian said. "If they are not above a certain threshold after their first 16 games, the odds are pretty good that they will not be a franchise quarterback. The odds are even stronger that they will wash out completely."

We have found strong trends among the 41 quarterbacks making their first 16 starts over the past eight seasons. The QBs with the worst performance metrics over those initial 16 starts flamed out. The fast starters reached the playoffs in every case, playing in three of the past five Super Bowls. Their futures appear bright. The QBs in the middle look as though they'll remain there in the majority of cases.

Every situation is different, of course, and many factors dictate whether a quarterback ultimately succeeds, but there have not yet been many exceptions to this general rule.

What do the numbers tell us about the league's newer starters (including RG III, Foles and Geno Smith), and the QBs who enter the 2014 season at a crossroads (including Bradford, Newton, Stafford and Dalton)? Let's take a look.

The seven fastest starters are on their way

A four-year body of work allows for definitive evaluation in most cases, and Total QBR agrees.