One thing that the people who are bringing up the Kings, Clips etc. are missing is the opportunity. I'm sure that 29 teams in 2007 wanted Oden, and given the 2nd pick with Oden off the board, 28 wanted Durant. Doesn't matter if ATL's GM just knew that Durant would blow up and be a super-stud and be better than Horford. He didn't have the chance. He had to roll with less-sure/lower-ceiling options.
Joe Dumars messed up in taking Darko over Wade/Melo/Bosh. But he had that chance. DEN got lucky and took Melo. Doesn't matter if TOR knew that Bosh wasn't going to be as prolific as Melo, they didn't have the chance to get him.
You can go down the list. People keep bringing up Webster and CP3 and will until the end of time. But we had the opportunity. the Jazz had the opportunity to trade with us because they had a good pick as well. The L*kers, for instance, couldn't say "Man, we really want CP3/Deron next to K*be--let's get him!" They didn't have the opportunity with their pick or assets enough to trade for him.
As the draft progresses, it becomes more of a crapshoot. Lots of us wanted Drummond or Barnes with our pick in the 2012 draft. But we didn't have the opportunity. Would you rather have Drummond and 3 more losses in 2011-12, or Leonard? And there's much less of a chance that Drummond becomes a HoF than, say, Davis. The Knicks really wanted Steph Curry with the 8th pick, but they didn't have the chance because GSW won one fewer game than they did, and were stuck with Jordan Hill.
There are myriad permutations and ways to get good, but one of them is that you need superstars. It's significantly harder (due in large part to opportunity) to get a superstar the later you draft. Not impossible, as has been shown by multiple teams. But bringing up Kings/Clippers/Nash's drafting to state why winning an extra couple games a year doesn't matter isn't really making the same argument.