I think we probably notice the exceptions (whether poor and great work ethics) when it's possible most people (even the teens) fall somewhere in the middle. Most of us are passionate and devote an exceptional amount of effort on something. It's just not always work (or school).
My son was a terrible student. He scored just below the cut off for his elementary school talented and gifted program in first grade. Since that cut off differed (and still does) depending on your state, district, or school, he might well have been accepted into the program if we'd been elsewhere ... or if teacher's recommendations had been considered. I can't tell you how many times his teachers told us through the years that he was bored and wasn't challenged in school. Even when he did his homework, he often didn't turn it in. I wish we'd challenged the decision not to place him in the talented and gifted program.
But, if you thought he was lazy, you'd be so wrong. I was amazed at the amount of research and effort he put into things he was interested in. When he started playing Dungeons and Dragons, he was his group's Dungeon Master and spent hours researching and planning their adventures. While other parents were upset over how much time their kid's spent on D&D, I was glad to see my son so strongly committed to something that was teaching him valuable skills. Absolutely, I wished he'd have put a fraction of the effort into his grades and schoolwork. But if he wasn't going to learn these skills in class, at least he was learning them somewhere!
Granted, I think earlier generations (those who were adults before the 20th century), probably had the best work ethics. At least ... the "common" folk The filthy rich folk spent their days lazing about or flitting from social fling to social fling ... or bossing the help about :wink:
When people depended on growing and raising their own food, if they didn't have a strong work ethic, they starved. It wasn't until life got easier for the average person that our work ethics started slipping. Once we all started having more time available for fun and leisure activities, our priorities started shifting away from devoting our lives to work.