Yes, I'm sure they have a baseline "performance" expected, by time of day, type of product, and average viewership for the time of day.
The more aggressive they become, the more they return to some products shown already, the more you feel they are struggling to hit the mark.
Just as you know that the things which they have the deepest stock of will be the ones they demo the most.
At one time if the guest or presenter was wearing something that would sell out fast, often before they got to it in the colour worn. Now not so much.
With so much of what they sell they are neither offering what their loyal customers would like to wear, nor what their desired customer prefers...and often not only the presenter and guest look awful, but the slim leggy models too.
Some customers will buy because they like the presenter or guest, or because they are heavily brand loyal ..but even they will think again if being let down by the product in their hands happens often enough.