The newly promoted club are second from bottom, with only Sheffield United having a worse record this term.
"Do you know what, they've been dreadful. They've been dreadful," said Keane on Sky Sports.
"We talk about teams having a style of play in the Championship and trying to compare it to the Premier League, it's chalk and cheese. It's impossible. They look weak physically.
"The goals they're giving away, it's schoolboy stuff. They gave away a goal against Arsenal last week.
You wouldn't see it on a Sunday morning, it's dreadful. I admire managers who have a philosophy and a style of play, but you've got to adapt. They've been nowhere near good enough, it's embarrassing the way things have been going for them."
"That's when you progress most. Every book says it. It's just really rough to be in it. But that's why you get better," said Kompany in response.
"The absurdity of this job is I probably feel I've improved more this year than I ever have in my life.
"But, because you're judged by results, you're probably not having to tell this story until you're back having your wins. These moments are useful, they're just not nice."