A Novel vs a Series

There are a lot of mixed opinions about having a series of books or just a single novel.  When I read a book I always want to know what happens next.  My mind comes up with all kinds of different endings, but in the end I am never quite satisfied with how they turn out.  The first book is without exception my favorite.  However, in some novels there are just one to many loose ends or gaps that need to be filled.  Even though I know I'll like the first book more that doesn't mean I won't buy the second or third.  The anticipation of what might happen is constantly there filling me with excitement.  Because even though I won't like the book as a whole there are a couple of bits hidden in the pages that I cherish.  Those small parts might be just a few lines but to me they are worth the wait.