Pillowtop is a method of construction, not a comfort designation, much like tight top, Eurotop and box top. While pillowtops are often represented as being plush items and their own level of comfort, the overall softness will be determined by the amount, type and hardness (Indentation Force Deflection – IFD) of the foams contained within the mattress, not the method of tailoring/construction. I could create a mattress using multiple layers of very firm polyurethane foam and tailor it as a pillowtop and it would be quite hard feeling. Take that same mattress and replace that firm foam with plush polyurethane foam or some memory foam, and the same pillowtop constructed-mattress would now be very soft in comfort.
Ideally, tailoring a mattress as a pillowtop would be desirable when there is such a volume of comfort material atop the support unit of a mattress that it behooves the manufacturer to bisect these layers in order to create more structural integrity within the mattress. Unfortunately, too many manufacturers choose to design mattresses unnecessarily as a pillowtop, quite often because of the perception of value and name cache that the term “pillowtop” carries. Hard, soft, or ultra plush are all terms that describe a relative level of comfort, but pillowtop should not be included in that list. If you have a customer asking you for a pillowtop mattress, take a few minutes to listen and really determine what they mean by this so that you may assist them in finding a product appropriate for their needs.