They are not a different category. This is a distributed database, network errors and node failures are a fundamental part of its function.

Fundamentally every distributed protocol has a moment where it may have to tell the client it has abandoned the operation, but already has in flight messages to remote replicas that would result in a decision to complete the operation.

Before that operation is answered by the replicas, the operation is in an unknown state. It is fundamental. Some slower approaches to reaching decisions may mask this problem more often, but it is there whether you realise it or not.