One time - years ago I was working late and by the time I got ready to leave, the elevators had stopped working.
No cell phones existed back then and there was no emergency number that I knew to try.
I thought about it and finally, I decided to walk down the stairs. I was on the 48th floor!
My legs were like jelly when I came to the end of the stairwell UNDER the building ... then had to go up a couple of flights on the other side of the building ... in order to actually exit the building and walk to the parking lot. I had to sit on the curb for 30 minutes before I git the energy get in my car and drive home.
My days of working late ... were over.
I never stay in empty buildings alone.