Question:

Why is the Sample Recipient field sometimes displayed as a Radio Button and sometimes as a Drop Down menu on the Call UI Pages?

Answer:

How the Sample Recipient field displayed on the UI is depends on the --asf section signal on the Attendee Notes section.

If the --asf section signal is added, then there is a drop-down menu. If the --asf section signal is not added, then a radio button is used.  Whether to use the section signal or not is simply a design choice and does not affect functionality.

Related Documentation:

CRM Help Article: Zvod Fields Not Displaying in Conjunction with the --asf Section Signal in CRM

CRM Help Documentation: Section Signals