I recently bought a Sleep Innovations Marley mattress on Amazon and I've slept on it a couple of times. It's super comfortable for me and I have no complaints with respect to that. However, my queen-size mattress is a little under 78 inches long, which is a problem, because so am I, and my feet hang off the end of the bed when I stretch out.
About five years ago I bought an inexpensive twin mattress from a similar brand on Amazon, and it was also a couple of inches too short. I didn't care about that, because it was for my daughter, who was 4 or 5 at the time--it worked fine for her then and still does, so it wasn't worth the hassle of a return or an exchange.
But this gets me thinking, are the mattress companies doing this on purpose? My new mattress hits the advertised width, and most people would probably notice if their mattress didn't. But how many people are going to notice if their mattress is a little bit short? The huge majority of people just aren't that tall. And it seems that shortening every mattress by an inch or two could lead to a not-insignificant reduction in material costs for the manufacturer when spread out over a large number of units.
Potentially damning--the knit cover seems to fit my mattress perfectly, suggesting that the mattress is exactly the size it was designed to be.
Anyway, does anyone have insider knowledge or personal experience to support or refute this? Are mattress makers intentionally selling us short (ha).?