I can't really chose an answer. I have always been author oriented. Until recently, I have not had the luxury of being able to find books to read in chronological order.
I have lived in towns with no library, no internet (not even dialup as the phones were radio phones) and not a single book being sold. And this is within the last 5 years. I depended almost solely on the kindness of strangers passing through
Currently I have an internet connection, and there is a one room library with a good 20 bookshelves
Some of these shelves even have books on them, although I have read most that aren't dictionaries.
I disgress perhaps, but a few years ago if I saw a book I hadn't read by an author I enjoyed I would offer the poor unsuspecting traveller double the cover price. Sometimes they said yes, sometimes they didn't. Sometimes they gave me all the books they had read and brought more the next time they were through. Strangers are often kind.
Obviously my criteria is not as stringent as some.
Series books like Spenser, Sookie Stackhouse, Jack Reacher, Harry Bosch, Stephanie Plum, John Taylor, Mathew Scudder, and many many more, I like because I have grown fond of the characters. I will eventually buy or borrow any unread books because even if the characters have become stagnant after the first 10 or so books, or I was stupid enough to read too many books in a series in a row I still like them.
Take Robert B. Parker's Spenser for example or Simeon R. Green's Nightside. After x books what can you do to develop the character, plot etc. Read six in a row and it gets a little old. Haven't read one in a while and it is like water to a parched plant.