This is NET, not kenpom or sagarin. No one starts based on name or last year's performance.
NET is based entirely on current season actuals - which means early season you see teams beat up on cupcakes and soar to the top, then lose their next game and plummet. We're still less than halfway into the season, so a bad loss can still have double-digit swings. NET is much more volatile, because it doesn't have a cushion of prior season data.
It's like a kid who gets a 100% on his first math quiz that is mostly review material from the prior year.... are they an A student? At that moment, yeah. If they get a 50% on their next quiz, though, that GPA drops fast.
As the season progresses, reality starts to emerge as more and more data points are added.