Some teams that flashed some potential en route to the NBA postseason will be sorely disappointed in how they perform there.
It's not quite accurate to predict that, say, the Dallas Mavericks will fall apart against the San Antonio Spurs. Such a claim discounts the quality of the opponent. San Antonio is so good and so methodical on both sides of the ball that Dallas won't have any response.
Granting that the Mavs are a very good team this year and better than nearly everyone in the East, that wouldn't be a collapse. A much better team would be doing what it's supposed to. That's a dismantling.
The true disappointments will be the squads that have a shot to do some damage in the playoffs, even if it's as an upset threat, but fall short. These won't just be the teams that lose, but the ones whose losses will haunt them into the offseason.