I don't believe the only barometer for judging a team's success is championships. Professional sports is a business first, people don't buy into teams for the sole reason to lead the team to a championship. Maybe Mark Cuban used to think of the Mavs as his toy but now he is all about the business
You have a lot of championship-less teams in the league and they are still money making machines. Maybe not as much as the NFL teams but there is still money to be made with or without the trophies...... especially if you factor in cities willingness to bond out or give teams stadiums to play in for little or no out of pocket money. Compared to teams like the Clippers, the Suns are a complete success.
These owners have it pretty good.... they have people that live and die by their product and get into fights on internet messageboards about their businesses. These owners could give two ***** about you and or ever winning a championship. People like the Bidwills, Carl Pohlad, Jeffrey Loria, etc could careless if they ever win a championship as long as they are gettting their revenue sharing and TV money