Cameron Schlehuber wrote: >Rich makes an excellent case for the kind of changes that would lead to a >higher probability of success. Here are a couple of articles that describe >to a "T" many of the reasons how and why we succeeded with DHCP, ne VistA >(years ago when packages were re-tooled every 6 to 18 months) . and are >terribly bogged down today, some 12 years after a "no new versions" >direction and some 6 years after "a single Waterfall is the only SDLC >[Software Development Life Cycle] to be used." >www.adtmag.com/article.asp?id=10856
The utter inappropriateness of the Waterfall model for the development and maintenance of complex long lived information systems is painfully and blindingly obvious. There must be literally thousands of examples in VistA alone of the ongoing need to modify applications and data structures (sometimes drastically) to meet changes in new technology, in regulatory and administrative requirements, in user capabilities and expectations, in the practice of medicine, in the understanding of the problems to be solved, and in the understanding of how the whole system is put together and how it could be made easier to develop and maintain to meet future needs. These quotes from the first article that Cameron referenced seem especially relevant: "In any language, they should design with the expectation that it’s going to need substantial refactoring within a couple of years or less" "there is no process on earth where the requirements don’t change, and if you’re in a waterfall process, they probably change by the time you get to implementation. So you pretty much need to start refactoring as soon as you finish." “An evolutionary design done right is about the best service you can do for a system’s maintenance costs over its lifetime” "If management does not see it as a problem, then no matter how good and effective the technical solutions are, they will never be implemented and we will carry on building our Frankenapplications." --------------------------------------- Jim Self Systems Architect, Lead Developer VMTH Computer Services, UC Davis (http://www.vmth.ucdavis.edu/us/jaself) ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_ide95&alloc_id396&op=click _______________________________________________ Hardhats-members mailing list Hardhats-members@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/hardhats-members
