Questions That Keep Me Awake

Fact: It's 3:23 AM as I am writing this post. 
Fact:  I cannot sleep, because certain questions plague me into the wee hours.  For example?  Please see the photo below:

This photo depicts a very boring portion of my apartment.  It's that wall that most apartments seem to have that houses things like a/c vents, the thermostat, the water heater, and that random lightswitch way at the top.  My question?   What does it control.  Seriously.  What?  It' s so high up there that most normal people would need a ladder to reach it.  Luckily, my ape arms allowed me relatively easy access and I flipped the switch on and off several times, but nothing in the apartment changed.  I flipped other switches on and of to see if they're being on changed anything.  It didn't.  The only light that it might control is the overhead light fixture by the entrance, but that's already taken care of  by the multi-switch panel relatively close by which does not sit inches away from the ceiling.    If I can remember to call my apartment's office tomorrow, perhaps this question will be resolved.
Joe Hartman