Now I do not know the exact details but this is what I got from the steemit.chat welcome page when it was down.
He moved down in the witness list which meant he would get a lot less money for being a witness, therefore he couldn't keep steemit.chat going because it's a pretty expensive thing to maintain.
His issue lies in that there is no clear space where it is all clearly outlined what the witnesses are doing on the blockchain.

I guess it's everyone's own personal opinion to decide if a witness is doing their job or not and to vote based on that.

I am just grateful that this predicament came up because I dived deep into the whole witness thing and am doing continuous research on them.
And based on that, people can make their own decisions whether or not to give them their vote. :)