Working hard, or hardly working?

Everyone has heard of the classic 'relaxed' European work mentality. In my experience, this is really the case here. It's not that I haven't seen my fair share of hard working people, because there are many. But every now and then I hear people make comments, or I hear stories like the below about those who don't want to work "too hard."

Case in point:
My colleague shared the story of his American neighbor who had a job in The Hague working in PR for a museum/curator. She lost her job unexpectedly, and the reason she was given was that she was making the other employees, including her manager, look bad because she was working 'more' than she needed to, & doing more than was in her job description. This is so ridiculous to me that I can’t even formulate a comment.

Another similar case:
A friend of mine (also not Dutch) received a call from his manager asking him not to work as hard at his job, at a hotel in the city. The other employees complained because he made them look bad. Again, this was a case of an 'over achiever,' or someone who was going to extra mile at work, even though it was not explicitly in his job contract. Instead of asking the other employees to use it as a good example, or work harder themselves, or even reward him for a job well done, they asked my friend to work less. Granted, he was working below his job potential, but they didn't have another job to move him into at the time, so they asked that he "work down' to this job level. Seems to me like they not only missed out on his potential, but some good quality work.

Obviously these are only two specific instances, and do not represent the workforce as a whole, or all companies. But still, I don't know how I would react if I was in either of these two situations. I think there is something to be said about putting in an honest days work and working to your full potential, not just simply sliding by. This is something that has been ingrained in me by my parents, school, & sports. I would not be happy, or satisfied with myself, knowing that I did not put in my best effort. I guess in every culture, you have a bit of both.

-S