If there are only a few left they more often think "what's wrong with these that no one bought them."Not necessarily. If there is a lot of them on the shelf, then the guest might think "I can wait a few more days/weeks and think about it and then maybe it will go on sale". They also might wonder if the product is any good because if there are so many then it must not be selling well. If there are only a few then they might think "I better buy this right now or else it might be gone"
Except during 4th quarter, then your argument applies.