It is often said that you learn more from failure than from success. When you win, you don't question how to get better, how to improve. When you lose, you're forced to analyze your process, and really think about how to fix what ails you.
When the Heat were beaten by the Mavericks in the 2011 NBA Finals, they were bested by a different kind of team. The Mavs practiced a "four out" offense, where four shooters spread the floor and Dirk Nowitzki dominated the action. Since then, Miami has gone down a similar pathway. The Heat learned from the Mavs, and they're adding new tweaks along the way.