[loramin]

When you use spells like Cure Disease or Abolish Disease they only remove a certain number of counters. So (using made up numbers) Cure Disease might only remove 2 counters, but Abolish Disease removes 6, so it would take two Cure Diseases to cure Affliction (4 counters) but only one Abolish Disease. Obviously this is only relevant if a mob casts a disease spell on you, (EvP) or when fighting other players (PvP); it's not so relevant in PvE because mobs don't cure themselves.

Hope that helps.