There are two main causes for kill stealing: the desire for the reward and the desire to cause other players grief. Kill stealing is predominantly done to gain the rewards from a kill. Griefers kill steal as only one of their tactics in annoying other players. However, there are side-reasons towards kill stealing, with a few being unintentional, i.e. killing an enemy with low player HP, and then killing another enemy - in a panic - which is being dealt by someone else.