All of their movies have had interesting ideas and terrible execution. In theory, "Martha", is a really good scene where an almost trivial detail humanizes Superman to Batman and makes him take a step back and realize that, holy shit, he's the bad guy now. All of a sudden he's no longer fighting a faceless mega alien too dangerous to leave alive, he's about to kill someone who's only concerned with protecting his mother. He's not Batman anymore, he's Joe Chill with a robot suit. On paper there's tons of great details in that scene, the use of the robot suit from The Dark Knight Returns, for example, basically borrowing the thematic visuals from that book to let us know that Batman is turning into a monster.

On screen of course it's two very burly men trying their hardest to sound serious while grunting the word Martha at each other. Sure that other stuff is there, but it's just the most awkwardly shot thing imaginable and the line delivery is terrible so it loses all gravity and becomes ridiculous.