A few times have happened where 2 agents where looking at the same ticket and its contents, and then one of them decides to assign it to themselves.
Then the other one, since they don’t know that it’s been looked at and assigned by another user, they inadvertently assign it to themselves.
The real disadvantage of this scenario is that they may both send their initial replies to the client without realizing what happened, which of course does not look good or professional to the client.