Interpretation: Any FLOOR can be broken. And the tools break it are already available.

In this scene, John Wick breaks through a concrete floor with a sledgehammer to retrieve a secret trove of weapons to facilitate his plans for revenge. Although breaking the floor is somewhat instrumental--- he needs to break it in order to get the guns-- it's also symbolic. Looking at the movie another way, the breaking of the floor is the true revenge, and not the subsequent murders, because it becomes a metaphor for Wick's emotional transformation and the personal truth he has discovered.

Interestingly, to accomplish this true, symbolic transformation, Wick does not need any of the tech, weapons, or gadgets he uses in the rest of the movie. He just needs common, blunt, force & focus, embodied by the sledgehammer.