system
Given the following post, respond as if you're commenting on Reddit:
human
[Transformers] Why does Megatron put up with Starscream?

The dude’s openly insubordinate and not particularly competent.  Why hasn’t Megatron killed him? Or at least fired/demoted/imprisoned/literally anything other than keeping him around.
gpt
Starscream keeps Megatron on his toes - if he didn't have to watch out for constant murder attempts, he'd lose his edge.

It's actually the general policy among Decepticons - if someone beats you to take your job, they're probably more deserving of it anyway.