Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!usc!ucsd!pacbell.com!att!cbnews!cbnewsm!lfd From: lfd@cbnewsm.att.com (Lee Derbenwick) Newsgroups: comp.software-eng Subject: Re: Second System Effect Message-ID: <1991Feb23.170522.2377@cbnewsm.att.com> Date: 23 Feb 91 17:05:22 GMT References: <30512@mimsy.umd.edu> <15369@megatest.UUCP> Organization: AT&T Bell Laboratories Lines: 37 In article <15369@megatest.UUCP>, pat@megatest.UUCP (Patrick Powers) writes: > In twelve years in the biz I haven't observed a second system effect. Perhaps the publicity it got in _The Mythical Man-Month_ actually _taught_ us something? And I think most professional software developers and managers have at least been exposed to the book. Also, most of today's software managers have been software developers long enough to see all (well, many of :-) the things that can go wrong with a project, and they are a little more hesitant to promise the sun, the moon, and the stars. These days, we are more likely to see creeping featurism: where each new release adds just a bit more, until we end up with a full-fledged indigestible fruitcake. Where I have seen something resembling second-system effect is when a hardware manager with no software background (and experience with only relatively small hardware projects) is given a small combined hardwware/software project. It's their first real dealing with software, so they tend to be _very_ careful, and they often succeed quite well. But based on their prior success, they're no longer so careful: they assume that everything that went well on the small project will automatically do so on the large one, that they can prevent those things that did go wrong from happening again, that effort will scale up linearly with project size, and that schedules will scale less than linearly, since they have more people doing the work. So, in bidding the project, they throw in every possible bell and whistle. They then run it using "What's-the-earliest-date-you-can't-prove-it- won't-be-done-by?" [thank you Tom DeMarco, for that phrase] planning, since that's the only way to get a schedule that matches their intuitive expectations. And they are honestly surprised when things don't work out. -- Speaking strictly for myself, -- Lee Derbenwick, AT&T Bell Laboratories, Warren, NJ -- lfd@cbnewsm.ATT.COM or !att!cbnewsm!lfd Brought to you by Super Global Mega Corp .com