As has been said, there is no loyalty from employers, especially in large organisations where you are just a number to those higher up the tree.
I know of a bloke was employed to do a certain job. Because of his skills he was able to complete the daily tasks much quicker than the previous incumbent so found he had time on his hands. Rather than just waste his time mooching around 'trying' to look busy he took to doing small repairs of equipment that used to be sent out for repair. He was saving the company hundreds of pounds each month, not intentionally, he was just trying to keep busy and justify his wage each month. Granted he was taking work away from another company but their charges were ridiculously high compared to similar industries further afield.
18 months or so ago a new department boss started and questioned everyone about their roles in the company. i.e. Job position and what they were expected to do etc. This guy didn't mention the 'extras' he does so the boss thinks he just does the one task each week. Very early in the year he, (boss), queried something with the employee which led to a protracted discussion which was eventually sorted out by HR and written into his contract of employment. Boss man was not happy as he had be shown up to be a bit of a bully.
Fast forward to present day and employee is still under pressure from this boss who tries to find fault at every opportunity with said employee. Employee has now submitted a grievance but feels he is not getting a fair hearing because said boss is very pally with those above him. These people have never met employee on a face to face level but they have often walked past each other in areas like the canteen or car park. He is now preparing to take this to a tribunal as he expects the decision will go against him and life will become unbearable and untenable. That's how little those at the top of the tree think/know about those below them. It's only when people like this employee go somewhere else that someone else is likely to realise what an asset they had been.