The travel desk is an effort allocation problem
A travel counsellor can build perhaps a handful of properly researched itineraries in a day, fewer during a busy week when the phone does not stop. Enquiry volume, particularly in peak booking windows, exceeds that comfortably. So the central question on a travel desk is not how to persuade people, it is which enquiries deserve a full itinerary and which need a quick indicative response and a call back later.
Agencies that never make that decision explicitly make it accidentally, usually by serving whoever called most recently. The result is a desk where genuine, ready travellers wait two days for a quotation while a counsellor produces the fourth revision for someone whose dates were never fixed. Qualification is the mechanism for making the allocation deliberate, and it takes three minutes.