You know how you always see those notices in elevators that say if something were to happen to the elevator you should call the mechanic whose number is listed? We're talking about the person who you would call. Elevators aren't just rooms on a string. They are complex machines that need complex problem solving when they break. That's why an elevator technician makes so much money - around one hundred thousand dollars a year.
It can be a tough industry to break into since you need to be generally good at fixing things. It's not a simple, one process fits all type of job. You need to be incredibly good at fixing machinery (both analog and digital) and great at problem solving, which isn't exactly something you can get a diploma for that instantly gets you a job. The job must be earned.