Did you know that druids have four different, viable playstyles? They can heal, tank, and DPS in two different ways. While others might be impressed with their flexibility, we aren't. Rogues have learned that complete dedication is required to be the best. Do you know what else doesn't heal? A shark. Do you know what never tanks? A viper. Do you know what always attacks from melee range? A wolf. Rogues channel their predatory instincts while concentrating on a singular purpose.
The only issue with being so focused on DPS is that we don't have any backup plans. What do rogues do when they can't kill things in melee range? If you're familiar with the Shazzrah encounter from the days of old, then you know that a rogue who can't attack is completely useless. My guild used to have all of us rogues light a few campfires in the back of Shazzrah's room and cook food for the rest of the guild while they downed the boss. After years of training to kill, I was stuck wearing an apron and making Savory Deviate Delights. Rogues need to do good DPS in order to validate our very existence.