I enjoyed Dune, but stopped after the first 3. I often do this now, as I have been disappointed by many of the longer series and bolt on extra books written to cash in on previous success. There are a host of these that I could quote - many by brilliant authors. IMO The Foundation Trilogy should have remained a trilogy, Jon Norman should never have written more than one of the Gor novels, (let alone the twenty something that he churned out) even the great Douglas Adams should have stopped after The Restaurant at the End of the Universe. I guess they get pushed by the fans, the publishers, and the potential noughts on the bank balance, to write more.
