Air traffic controller

 The difficulty of this job is clearly outlined when you first decide to go into that field, I'm sure they were very aware of the lack of sleep and hours that they needed to dedicated to their job.  Before applying for any position, specially one as harsh demanding as an air traffic controller, one should realize the amount of time they're going to have to spend for that field, and the pivotal fact that they aren't going to be able to get as much sleep as before. An air traffic controller falling asleep is a threat that can cause  serious situations, accidents and chaos in any airport.