Originally Posted by
Lyth
There will always be a relative shortage of tanks and healers. These are team-focused support roles. People pick these roles so that they can have an impact.
You don't need incentives to get people to play DPS. There's just less hassle, and you can play it like it's a single player game. The problem is that because the majority of the playerbase plays DPS, that's where the majority of the focus and effort goes. You want to have impact? Play DPS. You want to have first dibs on gear upgrades? Play DPS. You want job variety? Play DPS.
You're not really giving up that much control over how the fight pans out, either. Bosses move and position themselves, so tanks don't really tank anything. Outgoing damage completely scripted, so your healers aren't reacting and making critical saves so much as they are following a set of timestamps. Anything interesting in gameplay just comes down to dps, and as we've seen in the past two expansions, there's a widening gulf between 'support' roles and the main stars of the show. Why wouldn't you play DPS? It seems obvious, in retrospect.