Well, for a change, I agree with all of the above and they are spot on regarding "prevention of spread of disease" and "once the plant seeds, it will feel it has achieved its aim and pack up". This has always been true and I have always spent many hours weekly just on these two tasks ,,, removing dead flowers. The only thing that irks me is that if one notices in some areas where the local authorities spend well on floral dispays or the pubs that overdo it, when do you ever see anybody dead heading etc and some of the pubs have fantastic displays.