Ricky & Stick - Count the Right Things
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A software project plan is little more than a codified set of assumptions, expectations, and hopes. It typically contains some number of estimates based, more often than not, on optimism. Yet the sheer statistics of software failures, especially IT failures, would suggest that a healthy dose of caution, and probably of pessimism, would be more appropriate. *
Ricky thought he was being appropriately cautious when he estimated that, because he and Stick didn't always hit every one of their shots, they'd need ten snowballs each. But his reasoning was upside-down. He never once considered how many of their shots actually did hit the target; as it turned out, this was certainly fewer than one in ten. In other words, the number of snowballs wasn't significant, but only the number of hits. (The reader will already have noted that, given Ricky and Stick's throwing skill, they probably shouldn't have been planning to barrage Wally with snowballs in the first place. But that's a different fable.)
The moral is that we need to stop counting the wrong things, and start counting the right things. Easier said than done, perhaps. But it shouldn't be all that difficult to take a long hard look at whatever initial estimates you currently have, and wonder “What are these numbers based on? What aren't these numbers based on?” There's a good chance that, somewhere in the answers to those questions, you'll be saving yourself from getting walloped by a whole lot of snowballs.
* There are many sources for such statistics. One source often referenced is Lyytinen, K. and Hirschheim, R., (1987), "Information Systems Failures: A Survey and Classification of the Empirical Literature," Oxford Surveys in Information Technology, Vol 4. However, there are many others, whose numbers vary somewhat, but whose essential conclusions do not.
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