No rookie enters the NBA fully ready to dominate through the rigors of an 82-game season.
Even the greats in the league who hit the ground running as rookies—LeBron James and Kevin Durant come to mind—continue to add to their skill set year after year.
There's a reason there's such a thing as a "rookie mistake," after all.
As players progress through their second and third years, that's when their overall skills should start coming into focus.
Here, I've highlighted 10 promising players in their second or third NBA seasons who all still stand to improve in (at least) one specific area.
Rookies were intentionally excluded from this list because it's just too early in their careers to know what's a trend and what's an early-career anomaly. Also excluded are young players who have already achieved superstar status, such as Kevin Love, Derrick Rose and Kevin Durant, because that's just nitpicking.
Note: Statistics and records are current through games played on Jan. 1. Players are listed in alphabetical order.
DeMarcus Cousins has an absolute world of talent, but he keeps proving time after time that he's yet to get his head fully on straight since joining the NBA in 2010.
ESPN.com's Marc Stein reported back as early as November of Cousins' rookie season that handling him was "proving to be an even bigger job for coach Paul Westphal and his staff than expected."
In 2012-13 alone, he's already been suspended for two games after getting into a confrontation with San Antonio Spurs broadcaster Sean Elliott and one game for hitting Dallas Mavericks guard O.J. Mayo in the groin.
Then, two days before Christmas, the Sacramento Kings suspended him indefinitely for "unprofessional behavior and conduct detrimental to the team." Granted, that indefinite suspension lasted only one game and one DNP-coach's decision, but that's still three suspensions in roughly 30 games.
When Cousins isn't getting himself suspended by his own team or the league, he's appeared well on his way to becoming one of the NBA's most dominant big men. He broke out in 2011-12 with per-game averages of 18.1 points, 11 rebounds and 1.2 blocks in only 30.5 minutes, using that 6'11", 270-pound frame of his to repeatedly muscle his way into the paint.
If Cousins begins doing a better job of keeping his emotions in check, he'll make the Kings look like geniuses for picking him fifth overall in the 2010 draft. If not, he could be on his way out of Sacramento before the trade deadline.
After the Denver Nuggets grabbed Kenneth Faried with the 22nd overall pick in the 2011 NBA draft, Faried rewarded them with the most productive season of any rookie in terms of win shares, according to Basketball-Reference.
Through 33 games in 2012-13, Faried boosted his per-game averages from his rookie season across the board. In just under 30 minutes, he's averaging a double-double with 12.2 points, 10.2 rebounds, 1.1 steals and 0.9 blocks per game.
There's one aspect of his game that could use some work, however: mid- to long-range shooting.
According to HoopData, Faried attempted fewer than one field goal per game as a rookie from 10-23 feet, shooting 18.8 percent from 10-15 feet and 33 percent from 16-23 feet.
He's hitting 38.5 percent of his 10- to 15-foot shots and 32 percent of his shots from 16 to 23 feet in 2012-13, but he's still taking nearly 80 percent of his field-goal attempts from within 10 feet of the basket.
Faried has been a pure energy player for the Nuggets, running in transition and finishing at the rim like a player with years more experience.
If he can develop a mid-range jumper and expand his shooting range, he'll become that much more of a matchup nightmare for opponents.
As Derrick Favors continues to improve, the now-Brooklyn Nets may end up looking like imbeciles for trading him (among other pieces) for Deron Williams in February 2011.
Despite playing behind both Al Jefferson and Paul Millsap in Utah's lineup, Favors has made his talents felt in 2012-13 more than ever in his limited playing time. In only 22.1 minutes, he's averaging career highs in points (9.4), rebounds (6.4) and blocks (1.6) per game while shooting a career-low 44.3 percent from the field.
His perimeter shooting skills remain very much a work in progress, and Favors also needs to continue developing his post-up abilities to make the most of his talents.
Favors attempted 217 post-ups in 2011-12 but only scored 0.71 points per possession on them, according to Synergy Sports (subscription required), ranking 123rd in the league.
He's attempted 72 post-ups in 2012-13 and scored 0.83 points per possession, ranking 41st in the league, but he still stands to improve the consistency and diversity of his post game. He's shooting a career-low 60.2 percent at the rim, according to HoopData.
Favors' insane athletic talents could help him develop into one of the NBA's most efficient scorers in the league, so long as he continues to develop his post-up game.
With Danny Granger, the Indiana Pacers' leading scorer, missing the entirety of the 2012-13 regular season thus far due to patellar tendinosis, Paul George has been forced to step up in his stead.
To George's credit, he's filled in admirably after struggling to find his footing in the first few weeks of the season. In December, he averaged 18.8 points, 7.6 rebounds, 4.1 assists, 1.7 steals and one block per game for the Pacers, shooting 45.8 percent from the field and 38.8 percent from three-point range.
One place George could stand to improve? His spot-up shooting.
In 2011-12, George scored 0.99 points per possession on his 222 spot-up attempts, according to Synergy Sports (subscription required), which ranked 123rd overall in the NBA. Out of the 953 plays he ran that season, 23.3 percent were spot-up attempts.
In 2012-13, with Granger still out, George's spot-up numbers have dipped a bit. Out of the 97 attempts he's run, he's scoring 0.93 points per possession, according to Synergy, good for 147th overall in the league.
George's shot charts don't lie. In 2011-12 and 2012-13, he's hit fewer than a quarter of his field-goal attempts from three to nine feet, roughly 35 percent of his shots from 10-15 feet and roughly a third of his shots from 16-23 feet.
Considering how many spot-up attempts he takes each season, if George begins converting a few more of those shots each game, he'll soon emerge as one of the NBA's top young forwards.
Three years into his NBA career, Blake Griffin has already vaulted into superstardom, largely due to the SportsCenter Top 10 dunks he throws down on a nightly basis.
Griffin has also already emerged as a nightly double-double threat with career averages of 21.1 points and 11.1 rebounds per game. He's one of the few players who drops 20-10 nights routinely.
For a player with Griffin's size (6'10", roughly 250 pounds) and athleticism, however, his career shot-blocking average of 0.6 per game is horrifyingly low.
To Griffin's credit, since coming into the league, he's been forced to compete with a shot-blocking machine in teammate DeAndre Jordan.
That doesn't excuse the fact that Griffin ranks outside the top 150 in the league in terms of block percentage in 2012-13, according to Basketball-Reference. He's blocked only an estimated 1.6 percent of the two-point field goals attempted while he's on the floor.
Pau Gasol managed to block more than a shot per game while playing alongside Andrew Bynum in 2011-12. There's no reason Griffin can't do the same next to Jordan. If and when he does, he's going to only further aid an already strong Los Angeles Clippers team.
Despite being the youngest player on this list at only 20 years old, Kyrie Irving has a legitimate claim to being the most promising, talented player featured here, too.
There's not much to criticize about a guy who can average 18.5 points, 5.4 assists and 3.7 rebounds per game en route to the 2012 Rookie of the Year, especially when you look at Irving's supporting cast in Cleveland.
If Irving eventually hopes to claim the throne as the NBA's best point guard (as Amin Elhassan recently predicted for ESPN.com Insider), he'll have to step up his effort on defense, though.
As a rookie, Irving's defensive stats were somewhat dismal. He ranked 447th in the league in allowing 1.03 points per possession in plays he defended, according to Synergy Sports (subscription required), allowing opponents to convert 48.5 percent of their shots against him.
In 2011-12, the Cavaliers' defense allowed a whopping 112.6 points per 100 possessions with Irving on the court, compared to 107.6 points per 100 possessions with Irving on the bench, according to HoopData.
To Irving's credit, his defensive stats haven't been as dismal during his sophomore campaign in 2012-13. Still, if he hopes to displace Chris Paul one day as the NBA's top point guard, he'll have to match Paul's effort on the defensive end of the court.
Out of any rookie drafted in 2011, Kawhi Leonard trailed only Kenneth Faried of the Denver Nuggets in win shares contributed in their rookie season, according to Basketball-Reference.
For the 15th pick in the draft, that's a none-too-shabby return on investment for the San Antonio Spurs, who acquired Leonard in a draft-day trade for guard George Hill.
Leonard proved to be an excellent floor-spacer as a rookie, shooting 37.6 percent from three-point range, but he could take his game to the next level by expanding his passing repertoire.
The Spurs don't expect Leonard to ever turn into Chris Paul or Rajon Rondo (he's a forward, not a point guard, after all), but Leonard posted only 70 assists in his 64 games as a rookie in 2011-12.
Of all rookies in 2011-12, Leonard finished 50th in terms of the percentage of baskets he assisted while on the floor (6.6 percent). He finished the year averaging just 1.1 dimes per game, and his 2012-13 average of 1.3 assists per game isn't much of an upgrade.
San Antonio coach Gregg Popovich made clear before the season started that he expects Leonard to become the Spurs' next star once Tim Duncan finally gives way to Father Time. As such, he'll need to evolve into a well-rounded offensive weapon in the way that Kevin Durant has in 2012-13.
During his sophomore season in 2011-12, Greg Monroe of the Detroit Pistons emerged as one of the league's brightest young big men.
He averaged 15.4 points, 9.7 rebounds and 2.3 assists that season and finished fifth in the voting for 2012 Most Improved Player. In 2012-13, he's averaging 15.2 points, 8.9 rebounds, a career-high 3.1 assists and 1.3 steals per game, but he has struggled with his shot (46.7 percent from the field).
Unfortunately, there's no one easy stat to quantify what Monroe needs to change most. It comes down to one word: aggressiveness.
Ever since his days at Georgetown, the biggest questions about Monroe haven't been so much about his talent as they were about his desire to dominate opponents on a nightly basis.
Like Blake Griffin, his career average of 0.6 blocks per game is alarming for a player who's in the post as much as Monroe. He has the talent to be a 20-10 type of player, but he hasn't proven capable of turning in those type of nights on a consistent basis.
Monroe needs to learn from someone like Kobe Bryant how to have a killer instinct in each and every game. Once he begins turning in more consistent performances while rookie Andre Drummond continues developing, the Pistons frontcourt will be one of the most dangerous in the Eastern Conference.
No discussion of Ricky Rubio can begin without praising his otherworldly passing ability, so let's start with the positives there.
Despite subpar shooting as a rookie (35.7 percent from the field), Rubio won the hearts of his teammates by finding incredible lanes through which to lace passes. He averaged 8.2 assists in 2011-12 before tearing his ACL in March.
That subpar shooting remains a concern, however, especially when he's 16 feet or farther from the basket.
Rubio attempted more than five shots per game from either 16-23 feet or three-point range in 2011-12, yet he only converted 34 percent of those looks from either distance. Through six attempts in 2012-13, he's yet to hit a three-point basket.
His three-point shooting average isn't terrible, but if Rubio became more of a consistent threat from downtown, he'd extend the range in which opponents would have to account for him.
If Rubio becomes known for struggling behind the three-point line, opponents could pack the paint, eliminate his passing lanes and force him to beat them off the dribble or with a jumper.
By trading Andre Iguodala for Andrew Bynum in the summer of 2012, the Philadelphia 76ers essentially admitted that it was time to turn the team over to the young backcourt of Jrue Holiday and Evan Turner.
Now that he's not competing with Iguodala for minutes, Turner's been averaging 14.6 points, 6.8 rebounds and 4.3 assists per game, showing flashes of the Player of the Year that he was in his days at Ohio State.
While he's shooting a career-high 44.1 percent from three-point range in 2012-13—something he's done by not focusing on shooting three-pointers anymore—Turner's shot mechanics could still use some work.
Back when she worked for the Philadelphia Inquirer, Kate Fagan (now of espnW) chronicled Turner's summer 2011 work with Herb Magee, the so-called "Shot Doctor." Fagan, a former University of Colorado player, explained how the placement of Turner's off hand needed to improve when he was attempting a shot.
He's gotten better after his work with Magee, but Turner's shot release remains a work in progress. His left elbow tends to flare out and delay the release on his jumper, where every split-second counts.
There's no reason to believe Turner won't keep improving after seeing the astronomical leap in productivity he's made in 2012-13, but he'll eventually need to develop a consistent jump shot to live up to his No. 2 overall draft status.