Minnesota TWolves
http://www.nba.com/timberwolves
Timberwolves as a franchise joined the NBA quite late, in 1989 to be more exact. The Timberwolves were no exception to the rule of teams struggling when they join the league. Until 1995 they were mediocre at best and they were desperate for success. In that year's Draft, they selected Kevin Garnett with the 5th pick overall and things would change forever for them as a franchise.
In 1996 they made their first playoffs appearance, despite the fact that they were eliminated immediately in the first round, that was a positive change. Despite making the playoffs multiple times during the span of the next few seasons they failed to go deeper than the first round. However, that changed during the 2003-04 season where they managed to go all the way to the Western Conference Finals, only to lose to the Lakers, four games to two.
In 2007, they traded Kevin Garnett to the Boston Celtics and that was a blow that it would take them a long time to recover from. In 2010 they traded for the rookie Kevin Love, who turned out to be a great addition for the team, but in 2014 Love signed with the Cavaliers and Timberwolves are still struggling.