The harsh reality of the recruiting cycle is that not all top prospects end up being stars. While the recruiting services do well with evaluating and projecting talent, some big names struggle after they make the leap to the next level.

Injuries, a coaching change, a blocked pathway to playing time or poor performance can hinder a career that seemed destined to flourish. High-profile recruits can flame out in a matter of one year if the program isn't willing to stick with them through tough times, but sometimes bad luck strikes, too.

We've identified six former top recruits who are down to their final shot in the 2019 season. Failing to produce at a consistently quality level would either cement their tenure as a bust or put them in a position where the coaching staff will need to opt for more impactful playmakers elsewhere.

Stephen Carr, RB, USC

Recruiting info: No. 3 RB; No. 20 overall

What's gone wrong: Despite a breakout freshman season, injuries have been the biggest story of Stephen Carr's young career. He missed five games in 2017 before requiring offseason back surgery that led to a slow start the next season. 2018 was marred by a poor supporting cast and hobbling ankle injury. His yards per carry dipped from 5.6 to 4.7, and the explosive, game-breaking runs dried up.

What must go right: USC has a deep backfield with Carr battling Vavae Malepeai and Markese Stepp. If healthy, Carr's a legitimate three-down threat who has the speed and balance to win the job. New offensive coordinator Graham Harrell must get more out of an offensive line that produced the 107th-ranked rushing offense in the country. Carr will feast with a huge year if those two things happen.

Joshua Kaindoh, DE, Florida State

Recruiting info: No. 3 WDE; No. 10 overall

What's gone wrong: A 5-star prospect with elite size, Joshua Kaindoh was behind star Brian Burns in his first two seasons with the Seminoles. In 21 games, he's amassed just 36 tackles, 11 tackles for loss and seven sacks. His athleticism hasn't translated from high school, as his 6'7", 256-pound frame looks more sluggish and awkward than close to dominant.

What must go right: There's an opening for Kaindoh to step into a starting role as a junior. He must improve his run defense and set the edge with regularity to earn early-down snaps. Then, he needs to sharpen his pass-rushing moves, as he relies too much on his natural mass to bully blockers. Earning the starting job through a leap in consistency could lead to redemption in 2019.

Shane Simmons, DE, Penn State

Recruiting info: No. 4 WDE; No. 41 overall

What's gone wrong: Stuck behind more explosive talent, Shane Simmons hasn't earned the playing time needed to produce in a significant way. He has just 24 tackles, 4.5 tackles for loss and one sack in 13 career games. What's more discouraging is that fellow sophomore Yetur Gross-Matos led the defense in sacks and tackles for loss last year. If Simmons performed up to his recruiting ranking, he'd have seen the field.

What must go right: The bad news for Simmons is he's still buried on the depth chart behind more productive players. Gross-Matos, Jayson Oweh, Shaka Toney and Daniel Joseph were all more productive than Simmons, and that doesn't include the incoming freshman class. He'll need to dominate any snaps he receives to force his way into the rotation.

Curtis Robinson, LB, Stanford

Recruiting info: No. 4 OLB; No. 60 overall

What's gone wrong: 2018 was supposed to be the year that Curtis Robinson took over as a starter after Peter Kalambayi departed the program. Instead, an injury limited Robinson to only two appearances. He's logged just 35 tackles in three years as a reserve despite boasting premier size and range for his position.

What must go right: The senior moved from outside to inside linebacker in the spring, and that could pave a realistic path for him to see the field. 2018 second-leading tackler Sean Barton retired in February, so replacing his production will be key. Robinson must stay healthy, but his upside to play the run and contribute in coverage thanks to his agility can lead to a breakout season.

T.D. Moultry, LB, Auburn

Recruiting info: No. 3 ILB; No. 98 overall

What's gone wrong: Supposed to be an early-impact player for Auburn's aggressive defensive front, T.D. Moultry has instead been glued to the sideline. Tigers head coach Gus Malzahn cited his lack of consistency as the reason for his lack of playing time, likely referring to the three penalties in his first 30 snaps of the 2018 season. Malzahn and the staff clearly don't trust Moultry's decision-making despite their youth at the linebacker position.

What must go right: His issues are likely more mental than physical. Offside penalties are easily avoidable, yet he had two in the first four weeks last year and was also whistled for roughing the passer. Moultry's discipline needs to match his tantalizing raw skill set for him to earn snaps in rotation with Nick Coe. Coe, however, led the team in sacks in 2018 and has shown no signs of relinquishing his starting job. Moultry has an uphill battle to prove himself.

George Campbell, WR, Penn State

Recruiting info: No. 3 WR; No. 19 overall

What's gone wrong: After toiling as a backup in a bad offense for three years at Florida State, George Campbell transferred to Penn State and retained immediate eligibility as a graduate. He had just 206 career yards with the Seminoles despite standing 6'4" and running a 4.36 40-yard dash coming out of East Lake High School in Florida. It's hard to say whether it was the lack of opportunity, surrounding cast or that Campbell simply wasn't good enough outside of being tall and fast.

What must go right: The Nittany Lions offer a good situation for Campbell to prove himself. Only two wideouts return from 2018 with more than 200 yards, and one is slot speedster KJ Hamler. Head coach James Franklin will need the veteran Campbell to make an early impact as prized sophomore WR Justin Shorter continues his own development into a reliable contributor. Campbell's route running and jump-ball ability will be deciding factors in whether he finally finds success.