Oa oral irrigator

This is the Oa oral irrigator I am using.

With a pulsating water pressure of 1,800 times per minute, it neatly removes debris from every nook and cranny, even in places that dental floss cannot reach.

No matter how thoroughly I brush my teeth, I still find some debris coming off when I use this. That probably means it doesn't reach every nook and cranny properly, right? That's why this is a real must-have item.