I think they lucked into too much success early on, and they didn't appreciate it. The organization had only been around for a couple of years when they drafted Shaq.
Similarly, the Thunder ownership had only been around for a few years before they moved to OKC. They inherited Durant, and they lucked into Westbrook. They took it for granted. If they lose Durant this summer, and Russ next summer, they'll start to realize how cold the NBA can be.