I understood everything.

When you assemble the furniture and at the end there are screws and boulders, so that the ready-made structure to the wall, you stand and think "nakera? I understand that the commodity, although huge, but at the same time sufficiently square and heavy not to fall.
But when during the cleaning, your wife says to you:
Do not forget to move the commodity and spray underneath it.
Everything comes to its place.