The ping pong balls have spoken, and the Cleveland Cavaliers will pick first in Thursday night's NBA draft. With the guessing game about who will go to which team reaching a fever pitch, it's worth remembering that draft prospects are just that: Prospects. Even consensus phenoms are not guaranteed success at the pro level.

This year in particular, the draft class is a muddled mess, with few big names and plenty of question marks. A look at NBA history demonstrates just how unpredictable picks can be. Here, five of the biggest recent draft busts:

Greg Oden (No. 1 pick in 2007, Portland Trailblazers)

Drafted before: Kevin Durant, Al Horford, Jeff Green, Joakim Noah, Marc Gasol

The Trailblazers, overlooking concerns about former Ohio State center Greg Oden's fragile legs — as a result of hip surgery in sixth grade, his right leg is longer than the left — took him with the top pick in the 2007 draft. Three months later, Oden underwent microfracture surgery to repair his right knee, and then missed the entire season. Nagging injuries would limit him to just 82 games over the following two years before he wound up without a job.

He's reportedly eyeing a comeback, though no team has signed him yet.

Darko Milicic (No. 2, 2003, Pistons)

Drafted before: Carmelo Anthony, Chris Bosh, Dwyane Wade, David West

Milicic was supposed to usher in an era of dominant, foreign-born talent that some predicted would radically alter the NBA. Instead, he wound up as the ugly duckling in a loaded draft class.

Here are the first five picks from the 2003 NBA draft, in order: LeBron James, Milicic, Carmelo Anthony, Chris Bosh, Dwyane Wade. Of that list, all but Milicic have made an All-Star and All-NBA team in their careers.

Though Milicic did manage to score 11.7 points per game during his (short) career, that's hardly the performance Detroit expected from the second overall pick in what was otherwise considered one of the best draft classes ever.

Sam Bowie (No. 2, 1984, Trailblazers)

Drafted before: Michael Jordan, Charles Barkley, John Stockton

Bowie's name is now synonymous with the facepalm, since he's the guy who the Trailblazers took one spot ahead of Michael Jordan. Portland is believed to have passed on Jordan because they already had enough guards and needed a center, hence they opted for the 7'1" Bowie.

Jordan went on to dominate the league, winning six titles and five MVP awards. Bowie went on to have five leg surgeries and average, in his best full season, just 15 points.

Kwame Brown, (No. 1, Wizards, 2001)

Drafted before: Tyson Chandler, Pao Gasol, Joe Johnson, Zach Randolph, Tony Parker, Gilbert Arenas

Jordan was on the other end of a big bust himself. As the Wizards' team president in 2001, Jordan made Brown the first high schooler ever taken with the first overall pick. Brown, considered a superstar talent despite his youth, never lived up to the hype, though he has hung around the league in bit roles ever since.

Michael Olowokandi (No. 1, 1998, Clippers)

Drafted before: Antawn Jamison, Vince Carter, Dirk Nowitzki, Paul Pierce

Los Angeles wanted a big man, and they got one in the 7-ft tall Olowokandi — even though Olowokandi had only begun playing basketball at age 18 at the unheralded University of the Pacific. He averaged just 8.3 points and 6.8 rebounds over his career, and never did anything nearly as cool as Vince Carter, the fifth pick in the draft: