Lately I've noticed a design feature that makes a lot of sense: lifts with an "open doors" button, but no "close doors" button, making it impossible to mix them up in a hurry. Why the "close doors" button was included in the first place I suppose we'll never know.
Mokalus of Borg
PS - Perhaps it's a feature left over from when lifts had to be operated manually.
PPS - These days it only serves to cause problems.