The first two standalone "The Walking Dead" episodes of season 4 showcasing the Governor worried the fans. It appeared that the Governor had lost the wickedness. The madness that he is renowned for. Not only that, but it also appeared that he had lost all the will to survive in the zombie apocalypse world. He wandered aimlessly on the streets until he stumbled upon Meghan, Lilly and Tara. Now, he had a purpose. The purpose to save this newly-found family.

In the previous of episode of "The Walking Dead" season 4, "Dead Weight," the Governor becomes the leader, reluctantly. Scott Gimple, the showrunner explained, "Rick and The Governor are both fighting becoming leaders in this world because of what it exacts from your soul. He does get these unbelievable, brief flashes of happiness, impossibly after everything he's been through and after everything he's put people through. Love and circumstance brings him back to being the monster again," via Wetpaint.

David Morrissey (The Governor) in an interview with Entertainment Weekly, explained why he killed Martinez and Pete.

Why the Governor killed Martinez in "Dead Weight?"

Morrissey explained that why the governor got rid of his old buddy, Martinez. Martinez made the mistake of admitting weakness. "I'm not sure I can keep this place safe," he says to the Governor.

Morrissey said that if Martinez would have convinced the Governor that he would do anything to keep the place safe, the Governor would have said, "Great I'll follow you." But Martinez gave in, and the Governor took control. The Governor screamed, "I don't want it!" and killed Martinez. Gov. doesn't want to take responsibility. But he was forced to become the leader because of Martinez's weakness. He doesn't want to become the king but, guess what, nobody else but the Governor is worthy to become the leader.

Why the Governor killed Pete?

Morrissey explained, "The reason he kills the brother is because he doesn't want weakness. He's learned from the past that weakness and doubt is a very infectious disease. So he gets rid of the weakness and goes for the strength and the strength is the other brother."

He killed the weakness of doubt. The Governor is good with taking tough decisions and that is why poor Pete is dead.