What? No. Maul was never on their level.
Oh he was. Remember that Palpatine actually risked blowing his cover by personally travelling to Mandalore to take Maul out. He could've sent Dooku or even gotten Anakin to go there, but he didn't. He went there himself and even said Maul had become a rival.
The only explanation is that Palpatine knew Dooku would fail if he went there and rather than wait around for Maul and Savage to come for his head, he'd break them first. Even then, Maul somehow escaped imprisonment and went into hiding for decades. He's evidently more powerful and resourceful than we give him credit.
It's worth remembering Palpatine was becoming wary of Asajj too, yet he just ordered Dooku to kill her. That's what started the whole arc which ends with Grievous invading Dathomir and killing almost all the Nightsisters.
Palpatine isn't the type to get his hands dirty unless there's no alternative and him travelling to Mandalore to take care of Maul personally is, in my opinion, no different to him luring the best warriors in the Jedi Order - the ones that would easily survive Order 66 - to his office so he can kill them himself.
