In Aptien requests, you have the option of setting up the workflow either linearly, where approvers are one by one. Or parallel, where everyone has to approve the request at the same time.
Approving all together
in case of All together approval, the request is displayed to all approvers at the same time. The request must be approved by everyone.
Approvals one by one
In case of one-by-one approval, the request is displayed to individual people. The request reaches the next person only after it has been approved by its predecessor. The moment any person in this chain does not approve the request, the request ends and does not reach the next approver.