At the end of the day, it's a group effort. It isn't unreasonable to expect each player to put in a certain amount of effort and preparation. This isn't a single player game, so the mentality of 'I DO WAT I WANT' is quite rightly dismissed by a lot of players. If we were talking about a game like Skyrim, then sure...people can play however they want without anybody ever claiming that they need to do things differently.

Yet we're talking about an MMO. If one player in a group is putting in the bare minimum amount of effort, they're making things needlessly harder for other members of their group. They're not getting paid to babysit and it isn't fair to expect them to bend over backwards and waste extra time and effort to carry someone who is not sufficiently prepared.