Because I've gotten a few asks that want to tell me all about showrunning or Gimple's genius, I feel compelled to point out a couple of things.
If a showrunner says, in an interview or at a convention, that they discuss plot lines with the actors, it makes them and (more importantly) the show look good in front of the fans. It doesn't make that statement true. The brand promotion for TWDU is "found family," which is a marketing illusion. Everybody isn't involved in every decision—TV production is hierarchical, not anarchy. People who make a beloved TV show fudge facts for the same reasons everyone else does: to make a good impression and to sell their product.
(If anyone has stumbled across my tumblr by accident: I work in scripted television, so I'm familiar with how a show is produced. I'm not fansplaining.)
Gimple went from supervising producer in S3 to showrunner in S4. That promotion is the equivalent of going from being a first year resident at a hospital to department head. It doesn't happen because the studio 'likes your ideas'—you don't have the necessary skill set or experience to make that large a career jump. It's a major sign that something was afoot BTS during S3. Gimple took advantage of a terrible situation for personal gain; that’s how he’s failed upwards and is still there despite running the show into the ground in S7-8.
There's also a reason why people who've worked on TWD will still talk about Darabont but they don't mention Mazzara. Just like how the agreed upon explanation for Melissa's absence in DD S1 was that it was "logistically untenable" for her to relocate, the same is true for Mazzara and his "failure to produce." Saying that he didn't complete scripts on time is less of a problem for either party than the actual reason he was fired.
I've danced around this topic before because every time I see a fan of the female characters/actors praise this showrunner, I feel nauseous. But in plain English: he's a sexual predator, not a champion for the downtrodden. There are more than a couple of stories about him circulating among female creatives, but here's a screenshot that's directly relevant to TWD:














