This depends on whether an agent is a part of groups for which availability is managed centrally by admins ( can be configured under Admin-> Groups)
Case 1- Agents have the ability to manage statuses
If agents have access to change their availability in all the groups that they're a part of, they become unavailable for automatic assignment when they log out.
Case 2- Agent's availability is centrally managed.
If an agent is a part of one or more groups where availability is managed centrally by Admins, the agent's availability prior to logging out is considered for automatic routing.
For example, say Agent A and Agent B are part of groups where availability is managed centrally by admins. Agent A's status is available when they log out. Agent B's status is unavailable when they log out. Tickets will continue being assigned to agent A since they were available at the time of log out.