system
Given the following post, respond as if you're commenting on Reddit:
human
[Predator franchise] what is stopping a lazy, dishonest Predator from killing a weak human, stealing his skull and making up a story how the skull belonged to a powerful warrior?

I have seen Predator, Predator 2 and Predators. Afaik it is common to send a Predator on the hunt alone, and give him weapons to use as he sees fit. The predators do have an honor system and they are expected to pick the toughest, most powerful enemies, but besides this honor system is there anything else keeping them in check? What if a predator decides he wants the bragging rights without having to work for them?

What if he decides "I want the respect, but I really don't want to get shot at, or do the work of scouring the Earth to find the toughest, hardest humans I can find so instead I am gonna go to the suburbs, find some couch potato who never fired a gun in his life, take his skull, come back home, and say the skull belongs to the deadliest outlaw in all of America? Their skulls all look the same, so my buddies won't tell the diffrence. 

If I remember correctly, they only bring back skull of the human, and there is no way to tell if a human skull belonged to a couch potato, a highly trained commando, a hardened experienced police officer or a ruthless drug lord.
gpt
Funnily enough, this is sort of the big twist of the head-scratching "Archie vs. The Predator" 

Throughout, the Predator stalks and attacks ordinary teenagers or innocent townspeople; while they were always holding weapons at the time (i.e., a knife used for carving cake), nobody with half a brain should have interpreted them as real threats. 

We eventually learn this is because this specific Predator is... a stupid teenager who is out of his depth but is trying desperately to impress girls.