DEXTER Finale Season SPOILERS
According to Vulture, Dexter producer John Goldwyn had a few things to say about the finale:
"They won't let us kill him," he told us. "Showtime was very clear about that. When we told them the arc for the last season, they just said, 'Just to be clear, he's going to live.' There were a lot of endings discussed because it was a very interesting problem to solve, to bring it to a close. People have a relationship with Dexter, even if it doesn't have the size and the ferocity of the fan base for Breaking Bad. But it has a very core loyal following."
After this little piece of information. You get the sense that the writers never really had free reign on the characters and whatever kind of ending they had originally envisioned. Wasn't the one that the show ended with.