READ this and voice your thoughts

Okay IP members, here we go...
I have been on IP for probably a full year or more now and I totally love IP.  I have nothing against the site and all of the people on there are usually really nice.
But really, let's talk about the book swapping.
I know that everybody always has a lot to do and a lot of people to swap with, so I understand when people can only read the first chapter of a book, leave a comment, and then move on.  What I don't understand is this: there are people who will leave comments on your work and say that they "love it" and "wanna read more" but they never return to the story!  I mean, I might not have a right to complain about this because I know I can't always return to a story I really like either, but I suppose that when you're the writer of the story it bother you when people who seem interested aren't.
So what is up with that? Does anybody know?  Putting aside that they might have other projects to read or are really busy, why would they not return?
I suppose here this is where the writer of the story is supposed to PM the person and remind them, "Hey, you left a comment on my book and I was wondering why you haven't returned to it."
The picking... I honestly don't know if pick lists are that significant because I don't know too many people on IP that get bored and decide to look at their IP friends' pick lists for good books.  Most of the books that are on pick lists are usually ones with high rankings anyways.
So yes, I realize that this was kind of like me just ranting on about how I don't understand how some people on IP, but I was just hoping that some other IP members like me would agree or be able to relate.  Please feel free to tell me your thoughts on this.
Happy writing,
LReneeS