Because the Miami heat and the San Antonio Spurs were such great teams back in the 80's and 90's?
From Wikipedia: http://en.m.wikipedia.org/wiki/List_of_NBA_franchise_post-se...
"Of the 30 current NBA franchises, 13 have never won the NBA championship. The oldest such franchise is the Suns (46 seasons), while the Royals/Kings and the Hawks have even longer championship droughts (63 and 56 seasons, respectively). Only 7 franchises have never been to the NBA Finals, the oldest of which is the Braves/Clippers (44 seasons), and again the Kings and the Hawks have appearance droughts that are even longer (63 and 56 seasons, respectively). The longest a franchise has gone without appearing in the playoffs at all is 15 seasons: the Braves/Clippers franchise from 1977 to 1991."
Only 7 teams have not been to the finals. That's not awful.
It doesn't change anything about the fact that only eight teams in 30 years have won the title, and seven have taken 29 of those. That's an extreme dynasty system. They clearly have nothing but an illusion of competition in which the radical majority of teams can never win.
Compare it to the NFL of the last 30 years. 16 individual teams have won Super Bowls during that time.
Or compare it to the MLB. 17 teams have won the World Series in 30 years.
That 30 years represents the modern NBA, since the merger, Magic and Bird sent ratings soaring, and Jordan + the rise of global media changed everything about the league.
Now you've got Chris Paul shuttled off to LA in a market-stuffing trade, you've got star players like Melo eager to join up with dynasties like the Heat, and other players like Kevin Love that can't get out of the backwater fast enough. They all know how the league works now.
Also, note that (28/30)^44 is about 0.048. So, if it were decided by a throw of a die, you would expect 1 in 21 teams to have a 44 year drought in reaching the finals.
15 seasons not in the playoffs is bad, though, (14/30)^15 is about 1:100,000.
A model that introduces some correlation between the performance in year X and that in year X+1 without the need of a cartel could easily increase that probability, though.
For example, one could postulate that a team's quality increases with the qualities of its players and with the time they have been playing together ("you cannot buy a winning team")
Only 7 teams have not been to the finals. That's not awful.