I have always enjoyed a series more than a stand-alone book. I am a character-driven reader. I always want to know what happens next with characters, so a series where I can really get into their lives usually answers all the questins I have about what happens next.
The problem I am noticing is a few authors have a series about a character but really nothing for that character to do. The series becomes drawn out, the character does things that don't make sense, and the reader is tortured by seeing the character destroyed.
How many books about a particular character is too many? Do writers drag out a storyline to sell more books?