Some approvals have more than one possible person that can approve.  Each of these persons gets the approval notification and either one can go in an approve.  

In this scenario (multiple possible approvers for one approval "Role") we don't know which name to show as the approver until after one of them has approved. We therefore show "TBD" or "To Be Determined" while the approval is pending.  Once one of the possible approvers approves, their name will show instead of TBD.