Sir, that is the incompetent ones. The competent ones won't say a thing until it's over and they have no chance of taking a penalty or hit. The. They will hint at their own involvement to those close to the victim or the victim themselves without ever giving enough to prove a thing.

A competent malevolent being doesn't care for gloating until the deed is done. Long monologues in front of a hero aren't really a thing. Especially not as often as Hollywood would have you believe. An anonymous letter to the hero's family or group that explains how they died without saying who did it in vague ways that implicates tons of OTHER people, including the same family or group: that is the sign of a malevolent being who is competent and intelligent.