If you drag a control handle on a door shape, you can open and close the door. Here that lets you see the furniture is too close to the door.
All shapes in Visio are either 1-D or 2-D, depending on how they behave. However, some shapes have more behavior that is unique to them, and that does not depend on whether they are 1-D or 2-D. This makes these shapes especially handy.
For example, some shapes have yellow control handles
that let you interact with them. In this illustration, the door shape has a control handle that lets you swing the door open and closed. Will it clear the table nearby? It appears not. Better find a smaller table or make other adjustments to the furniture so that this problem doesn't occur in the real world.
Control handles aren't the only sign that a shape has special interactive behavior. Some special behaviors can be found by right-clicking a shape.