Responsibility is a pretty heavy concept, when you really think about it. It's more than just doing what you're supposed to do. It implies a greater understanding of what is needed and being willing to step forward to get things done.
When you enter the school system, you eventually come into contact with those dreaded group assignments. And for some reason being "responsible" more often than not translates into "trying to do everything yourself", especially if you're particularly conscious about your grades. It is said that given any group of people put together, a leader will emerge. School projects always help demonstrate this to full effect, although the leader tends to be the one who has the most anal parents or something. In order to be "responsible" for your own grades, it's worth putting in more work and pick up the slack from your classmates.
As you progress through life, your sense of responsibility tends to contract back onto yourself and only those people you value most. When you assert yourself over others out of a weird sense of community responsibility you stand the risk of stepping on other people's toes and offending one person or another. Being proactive can quickly become meddling. Advising friends can become acting like a know-it-all.
What are you truly responsible for? Should it be exactly the same for everyone? Is it okay when some people do more for others while it feels like others just sit back and enjoy the benefits of your initiative? Why do people treat responsibility in so many different ways? Didn't they get a chance to earn certificates as kids?