what I have heard. He is an arrogant bully. That's how he was pitched. He apparently has no time to listen, but plenty of time to just plain criticize, with no positive feedback whatsoever. And, which is actually worse, no feedback on how to change what he perceives as something wrong. So people are just left hanging wondering what they should do. And that is why I suspect folks are just leaving..
If it was me I would do the same. Why stay if you are told you are just wrong, but not why or how you can change it..
However the really concerning thing I did hear, was that he is for the most highly non communicative, to the point of being a total roadblock in significant areas. Again most likely another reason folks would leave. You cant work in a vacuum..
