In pro sports, these can make or break a franchise. These are the underrated players chosen low in the draft but who go on to have long, successful careers.
They can provide unexpected value to a team, pushing them into the playoffs or maybe even a championship.
But for every other team, these success stories can bring anguish to their fans and their front office: "How did we not choose this guy? How did we pass him up?"
In many cases, it's their size -- or lack thereof.
Take Boston Celtics star Isaiah Thomas. He averaged nearly 30 points a game this season and led his team to the top of the Eastern Conference standings. But because he's only 5-foot-9, he was chosen dead last -- 60th overall -- by the Sacramento Kings in 2011.
Even tall guys are overlooked for this reason. Draymond Green is 6-foot-7, but in the NBA that's considered small for the front-court positions he was projected to play. So he wasn't taken until the second round -- 35th overall, in 2012.
It worked out for the Golden State Warriors, though. Green's fiery competitiveness helped lift the team to an NBA title in 2015. This year, he led the league in steals and was an All-Star.
Location, location, location
There are, of course, other reasons that teams might underrate a player in the draft.
Maybe it's because they come from a small school.
Dennis Rodman, perhaps the greatest rebounder in NBA history, played at Southeastern Oklahoma State, located about 90 minutes north of Dallas, Texas, in Durant, Oklahoma. He went 27th overall in the 1986 draft.
Joe Dumars, one of Rodman's former teammates, was taken 18th overall out of McNeese State in Lake Charles, Louisiana, located between New Orleans and Houston, Texas.
played for the Detroit Pistons teams that won titles in 1989 and 1990. Both are in the Hall of Fame
Does experience playing in the US matter?
Maybe players have been overlooked because they weren't playing in the United States.
There weren't many basketball fans who had heard of Manu Ginobili or Tony Parker before the San Antonio Spurs chose them with late picks in 1999 and 2001.
Ginobili played for Argentine and Italian teams before the NBA drafted him. Parker cut his pro basketball teeth in France.
Now both men are household names and surefire Hall of Famers after leading the Spurs to four NBA titles.
Getting better all the time
Sometimes, there's not just one reason players becomes known as draft steals. Maybe they just get to the league and blossom, working on their game, fixing their weaknesses and finding the right role or team that fits their skill set.
Click through the gallery
above this story to see more low draft picks who became NBA superstars.