Every role has something they could be doing that they might not do.
Healers can DPS, but it takes a lot of familiarity and comfort to do without letting people panic or die. Similarly, tanks don't have to pull more than one group at a time in dungeons. You don't see it as much in leveling dungeons, but in the 50s and 60s it is entirely possible to grab multiple sets of enemies at once. It's also not necessary, and people WILL flip the fuck out if you pull something "wrong."
DPS don't have to AoE on big packs, either: They can single target one thing at a time when the tank has brought a dozen enemies to a boss barrier.
Everyone's got a comfort zone. I've had healers drop ten seconds into a dungeon because I had the audacity to cast protect as a paladin while they were... not buffing the group. Instead of seeing it as assistance, they took it as me undermining and making a statement.
Healers can DPS, but it takes a lot of familiarity and comfort to do without letting people panic or die. Similarly, tanks don't have to pull more than one group at a time in dungeons. You don't see it as much in leveling dungeons, but in the 50s and 60s it is entirely possible to grab multiple sets of enemies at once. It's also not necessary, and people WILL flip the fuck out if you pull something "wrong."
DPS don't have to AoE on big packs, either: They can single target one thing at a time when the tank has brought a dozen enemies to a boss barrier.
Everyone's got a comfort zone. I've had healers drop ten seconds into a dungeon because I had the audacity to cast protect as a paladin while they were... not buffing the group. Instead of seeing it as assistance, they took it as me undermining and making a statement.