My impression is that trade paperbacks really suck. Frequently the bindings crack when you open them for the first time. Mass-market paperbacks are not great but they have some minimum level of quality that is not certain in trade paperbacks.
No, I mean what I say. Mass market paperbacks are at a low standard but it is a standard. They are great to put in a backpack because of small size.
A good trade paperback is better than any mass market paperback but trade paperbacks come in various sizes and designs and many of them have serious defects when manufactured.
Ah, I see where the size standardization could be valuable. I was thinking only of quality, and everything I've read (and I don't mean I just went to wikipedia ;-), though they do actually agree) suggested that a trade paperback was closer to a paper bound version of the original hardback, up to and including the size and everything, and built consistently to a higher standard than a mass market version.
Some of them are good but some of them split at the back with the slightest bit of handling. Self-published trade paperbacks are particularly bad.
As a category I don’t like them though I have plenty of them. My favorite kind of sci-fi book to collect these days are small hardcovers but for nonfiction I take what I can get.