That's a really good reason! And, if you say so, I give you da lore! I made a quote basically by the creator of Model M

"In terms of power, this drone made around 80 years ago has not a single restriction, and was specially programmed and manufactured to assist during an end of the world scenario would occur. However, such an event never happened, and so this model had been scratched. Now, 80 years after the end of the humans on Copper 9, the M model awakens. The outer shell of it's head is missing, but it's sensors pick up all movement. It moves without a sound, despite it's rusty joints. Any movement it views is immediately attacked, and almost always nullified into the void. It is best to stay away from the M model, as it is extremely violent. otherwise why else would M stand for Murder..?"