The site doesn't allow for the wide variety of books that you might wish to catalog. For instance it doesn't allow for easy cataloging of a multi-volume series. Import function is quirky and inconsistent and cannot be customized (or at least no instructions are given for how to do it). I tried LibraryThing a few years ago and gave up on it after a few hours. Recently had another go and I don't think it's been improved or changed at all. Just not worth the trouble.