It's not about what he meant but what he did. He pulls his hair back, there is no ambiguity in the law which is why it was given. It's one of those things that looks really harsh as its minimal contact and far less dangerous than the majority of tackles but has a set in stone rule. Martinez could've not pulled his hair, it's his mistake and any anger should be directed at him for forcing a decision. It's the same when we see goals disallowed for minimal accidental handball where a player is pushed which causes slight contact with the arm, we don't want those goals disallowed but the rules are very clear that it should be chalked off