a disabled elevator

I'm pretty sure one of the elevators in my apartment has Attention Deficit Disorder. I've discussed this with other elevator riders and they all agree with me. Two of the three elevators in this building do what is required of them. They go up or down according to the buttons that are pushed, stop on the floors requested and generally behave like an elevator should. The other elevator seems to sometimes have a mind of its own. It may start going where you want to go - down to the garage for example, but them suddenly decide to go up again. It stops on random floors even if no one is waiting there, sometimes opens the door automatically, sometimes not. and generally seems to have trouble remembering where it's going. I have always, eventually, gotten where I want to go but it's often an adventure. I guess I should be grateful it hasn't figured out how to go sideways yet.