It's a common-sense principle: a car can't accelerate past traffic if it can't get out of the garage.
As training camp mode wound down and the Ravens' four-game preseason schedule began Aug. 13, that was the metaphorical challenge facing first-round draft pick and blazing-fast wideout Breshad Perriman.
Toward the end of the first full-squad practice, Perriman fell directly on his knee and sustained an injury that has been described as both a bruise and a sprain by head coach John Harbaugh.
"It's going to be a couple [more] days, I think," Harbaugh said Aug. 5. "It's just how he gets the range of motion going in there with the bruise and everything like that.
"I want him out here right now, [and] he wants to be out here, but [the trainers] are holding him back. It's probably smart. [The training staff] is smarter than Breshad and I are about it -- I know that."
The injury kept Perriman off the field for some time during the August training camp sessions.
But the fact that Perriman is an option for the Ravens at all is based on the good fortune of landing his services in the annual game of chance known as the NFL Draft.
Perriman's size (6-foot-2, 218 pounds), an eye-popping time in the 40-yard dash (4.2 seconds), his downfield playmaking ability at Central Florida and solid NFL pedigree -- he is the son of four-team league veteran Brett Perriman -- impressed the Ravens enough to make him their top college selection, using the 26th overall pick on him.
Even though the Ravens have used 23 draft picks on wide receivers -- more than any other position -- during 20 drafts, they have a spotty-at-best track record drafting receivers, more often ending up with underachievers, such as Travis Taylor, Mark Clayton, Patrick Johnson and Demetrius Williams, or complete busts, like Tommy Streeter, Devard Darling and Aaron Mellette.
The few that did stand out, such as the recently departed Torrey Smith, haven't come often enough to suit an organization attempting to achieve more offensive balance and at least partially shed its run-first reputation.
The 2014 season went a long way toward doing that, as the Ravens' offense set franchise records for points (409) and yards (5,838), while posting its second-highest amount of net passing yards (3,819) and passing touchdowns (27).
Smith contributed 11 of those touchdowns before leaving for the San Francisco 49ers as an unrestricted free agent. Perriman is seen as someone who can instantly fill the "X" (split end) downfield role opposite workhorse chain-moving flanker Steve Smith Sr.
But despite his speed and resume, Perriman knows he simply can't keep doing the same things he did at the collegiate level.
Adjusting to the speed of the game, running crisper routes, developing more stamina and concentrating enough to avoid the drops that have plagued his career are all important to him. Increased cardio training and learning how to line up in a more consistent stance that allows him to explode off the line have been the biggest steps Perriman has taken.
"I feel like I did good," Perriman said of his offseason program. "That was a main point of my training for the most part. I feel like I know when I get tired, my mind starts wandering, and things [don't] really go downhill, but I feel like I'm not as consistent. So that's something that I have been preparing myself for, and I feel like I'll do just fine with it.
"[Wide receivers] Coach [Bobby Engram] has really showed me a lot of things, especially with the release [off press coverage]. In college, you really didn't see a lot of [that], and I feel like since I got here, that's basically all you're going to get is straight press release.
"And he helped me a lot, tremendously, with my stance -- made me get more of a balanced stance -- and I'm more powerful coming out of it. So he has been teaching me a lot of great things."
Engram, who played 14 seasons in the league as a receiver with the Chicago Bears, Seattle Seahawks and Kansas City Chiefs, likes Perriman's work ethic, one that has been slightly compromised by the injury.
"The sky is the limit to how much time he's willing to put in," Engram said. "And he's a worker, and on the field, we just keep working the fundamentals, getting in and out of breaks, transitioning, tracking the ball, being aggressive back to the ball -- all the things he's working on since he started playing receiver."
Of all those who work with receivers, the one Perriman has to impress the most is the one throwing him the ball, quarterback Joe Flacco.
During the spring practice season, the strong-armed signal-caller got plenty of chances to put Perriman through the entire route tree, throwing him short slants and intermediate sideline routes as well as the spectacular downfield bombs.
Despite the occasional drops, Perriman did haul in several outstanding catches, prompting Flacco to feel good about the rookie's mental makeup.
"Everybody is going to make [mistakes], especially young guys," Flacco said. "We have to make sure that we work through them and they get tough because of it [and that] they don't go downhill because of it.
"I think [Perriman is] the type of guy that is going to react well to it, and he's going to want to go back out there and make another play, and I think that we've seen that so far. We've just got to make sure it continues to happen."
If it does, Perriman could put his name alongside the many young receivers who have made a considerable impact on the league in a short time.
In 2014, the rookie receiver class placed six players among the league's top 45 in receptions, led by the New York Giants' Odell Beckham, Jr., the Miami Dolphins' Jarvis Landry and the Tampa Bay Buccaneers' Mike Evans.
This year, Perriman's draft classmates include Kevin White (Chicago Bears), DeVante Parker (Miami Dolphins), Phillip Dorsett (Indianapolis Colts), Amari Cooper (Oakland Raiders) and Nelson Agholor (Philadelphia Eagles), all drafted in the first round. The second-round group wasn't too shabby, either, featuring Dorial Green-Beckham (Tennessee Titans) and Devin Smith (New York Jets).
Can Perriman meet the dual expectations of matching what that group does while proving to be, at the very least, an adequate replacement for Torrey Smith?
"Perriman, straight out, I think, is unbelievably fast," cornerback Jimmy Smith said. "Torrey will jog a route, and when the ball gets in the air, will take off on you -- can't catch him. But it's a different way they run the routes. Both of them completely [are] blazing. But just straight speed, I would have to see them race. But Perriman, that kid is fast."
For his part, Perriman puts the brakes on his own speed, saying, "There are a lot of fast guys [in the NFL]." Maybe Perriman is just being modest, or maybe he knows he's a rookie who, for now, has to know his place.
But everyone knows Perriman's career can't start until he pulls out of the garage.
Joe Platania has been covering professional football since 1994