There is a wonderful old Gary Larson cartoon titled "When potato salad goes bad." It shows a bowl of potato salad in a refrigerator holding up various other foods at gunpoint.
Projects don't go bad in quite the same way. But they smell as moldy as month-old potato salad when they do go bad. It's a smell that a good project manager can recognize even in the finished and launched project.
For example, I bought a bagel this morning at a grocery store that recently revamped its customer-facing point-of-sale/card-swipe terminals - those devices where you enter your "customer card" number, swipe a credit or debit card, and occasionally sign for the purchase. You can spot the first generation of these easily enough because (a) they're really, really slow and (b) they usually have scratched-up screens where some misguided customer signed with a ballpoint pen.
The chain to which this store belongs has had four customer problems since they installed the first generation of these machines. By customer problems I mean those that are visible to and annoy the customer, that mitigate against the good customer service this chain is trying to provide.
So for various reasons - e.g., slow, damaged devices - the chain has been replacing its customer-input devices with spiffy new ones. The new ones have brighter screens, pretty icons, and - at least so far - no ballpoint-pen damage. They also revised the software that runs them.
And therein smells the project.
The new systems address only problems #2 and #3 in my list above.
What do those problems have in common that #1 and #4 do not? They're purely mechanical problems, easily solved by "brute force," as programmers say - faster processors and next-generation LCD touchscreens.
Read more on the Lexician Blog.