I would put it differently, hence my aphorism that: "the sign of great architecture is not how well it does the things it was designed to do, but how well it does things you never imagined it would be used for". I suppose you could say that reducing maintenance and improving reliability are examples of the natural consequences of that, but to me those are limited special cases of the more general statement. My sense is that systems decline over time because of what I call 'system cancer': as they are modified to do more and more (new) things, the changes are not usually very cleanly integrated, and eventually one winds up with a big pile. (Examples of this abound; I'm sure we can all think of several.) Noel