It would be great to say that all employers are created equal and give their employees decent benefits, good working conditions, and pay them what they're worth.
Unfortunately, the employee, to many companies, is one of the most disposable of assets.
After all, there are plenty of people out on the street who will do the job for less.
If a company made an investment in training someone, why would they throw the employee's abilities and work experience out the door?
Too often it's a matter of short-term 'cost savings'. All done to boost the bottom line, impress investors and raise the stock price. Maybe the boss considers the employee a threat to their position.
In the end, the company usually has problems, but management is rarely to blame.
As long as the investors and upper management get to bail out with a profit, it doesn't matter that the employees lost their jobs and sometimes, their pensions.