I worked doing this for 7 years.
I didn't do just iphone screens, I repaired everything coming into the store, it was interesting because it was a different job every day.
Yeah you will do the same repair a lot of times, but also never-seen-before failures that keeps the job fresh and diving into the schematics, datasheets...
Then I moved to a huge electronics production fab.
They have almost everything for production, except pcb production (We order them to 3rd party): Pick&place machines for smd/bga/th parts, reflow ovens, wave soldering, x-ray view, tons of technical equipment...
Most people do the same thing everyday day, ex. putting the same screws, the same wires, the same plastic bezel... I'd shoot myself between the eyes!
I got the most interesting job in their fab: Testing, which is actually extremely boring compared to my old job.
- Hey, take this 40-page testing protocol and apply it to 400 boards. I get happy when something is not working as it should, because it's also my job to fix them.
So first we test all the boards, keep one or two fromt he working ones to compare signals/measurements against the ones failing.
Then the chaos starts. Sometimes we don't even have schematics. Some military boards are like that. "Put this parts, run this tests, and send us the batch. Oh, and fix the failing ones, but we won't provide any details". Simply ridiculous.
And when the production run is over, the only good part on my job starts. I can spend a whole day with a board if there's no hurry, taking my time to find the problems and fix them.
But the fact that only 2 years later I'm searching a new job, says it all. It's *** boring.