“Hadeet” means narration in arabic. The sects have hadeet-books that describes the pseudo-version of Prophet Muhammad, with his “companions” and even “early generations”, that they claim is Islamic.
The Kuran itself states “what other narration (hadeet) will you follow?”. (7:185)
Sects claim the illogic following external hadeet, when there were no such hadeet in Muhammads time, and he himself follows The Kuran. (7:203) (75:18) and his wifes (33:32)-(33:34). and that The Deity will explain it. (75:19). And “If they turn away, your only duty is to deliver the message”. (16:82).