Why did Roger Waters never get beyond The Wall?

So Rick sat in the studio -he would arrive exactly on time, which was very unusual, and stay to the bitter end every night. One day Ezrin said to me - he was slightly irked by this brooding presence very occasionally going "I don't like that" - "Why's Rick here again?" I said, "Don't you get it? He's putting in the time to prove he's a record producer. You talk to him about it." So he did. After that Rick never came to another session, unless he was directly asked to do keyboard tracks. And he became almost incapable of playing any keyboards anyway. It was a nightmare. I think that was the beginning of the end. 
But in the end of the end, since you ask, we had agreed to deliver the album at the beginning of October and we took a break in August to go on holiday. I sat down with a bunch of sheet music and paper and wrote out all the songs and what was needed and made up a schedule, and it became clear to me that we couldn't get it finished in the time available. So I called Ezrin, "Would you be prepared to start a week earlier on the keyboard parts with Rick in Los Angeles?" Eventually he went, "All right. Thanks, pal," -because of the idea of doing keyboard tracks with Rick. I said, "Look, you can get another keyboard player in as well in case it's stuff he can't handle, but if you get all that keyboard overdubbing done before the rest of us arrive we can just about make the end of the schedule." 
A couple of days later I got a call from O'Rourke. I said, "Did you speak to Rick?" "Yeah. He said, 'Tell Roger to f**k off.'" Right, that's it. Here I was doing all this work and Rick had been doing nothing for months and I got "f**k off." I spoke to Dave and Nick and said, "I can't work with this guy, he's impossible," and they both went, "Yeah, he is." 
Anyway, it was agreed by everybody. In order not to get a long drawn-out thing I made the suggestion that O'Rourke gave to Rick: either you can have a long battle or you can agree to this, and the 'this' was you finish making the album, keep your full share of the album, but at the end of it you leave quietly. Rick agreed. So the idea of the big bad Roger suddenly getting rid of Rick for no reason at all on his own is nonsense.

Gilmour: (Sigh) I did not go along with it. I went out to dinner with Rick after Roger had said this to him and said if he wanted to stay in the band I would support him in that. I did point out to Rick that he hadn't contributed anything of any value whatsoever to the album and that I was not over-happy with him myself - he did very very little; an awful lot of the keyboard parts are done by me, Roger, Bob Ezrin, Michael Kamen, Freddie Mandell - but his position in the band to me was sacrosanct. My view, then and now is, if people didn't like the way it was going it was their option to leave. I didn't consider that it was their option to throw people out.

Waters: I had a meeting with Dave in my garden in the South of France at which Dave said, "Let's get rid of Nick too." I bet he doesn't remember that. How inconvenient would that be? I went "Ooh, Dave, Nick's my friend. Steady!"

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