In Dead Island Riptide, desynching is a random occurrence that seems to be based on the connected between player and host. It seems that for some people, the host not operating the vehicle causes desynch.
A desynched player will act normally to themself, but to certain others, but not necessarily all, will appear as though idleing or continuing to perform their last ambulatory movement, like walking into a wall.
A symptom of desynchronization is that the group will not be able to progress past a certain mission objective which requires all players to be at a certain location. Another symptom may be that the desynched player cannot complete an objective, similarly, such as collecting all of quest items.
Is there an easy way to tell if one is desynched besides asking others if they see the desynched player as idleing?