There once was a woman who had great talent that built contraptions of all sorts. Devices to gather water, devices to keep their homes clean, devices to live their life better. People would come from far and wide to have the woman create them a machine. For the most part, the woman was also successful in keeping the contraptions running, despite the best efforts of the contraption users.

One day, a man from a faraway land came to seek the woman's renowned skills, and so asked her to build him a machine that would keep his shoes clean in the weather. "Easy enough!" the woman exclaimed and immediately set about building the contraption. Before the woman was even seated at her table, however, the man insisted, "This machine should also keep my socks dry."

Now the woman was not entirely seated yet, so she thought to herself, "I've not even begun, and so I will redesign my plans to incorporate this new contraption." She immediate set about her work.

However, it wasn't but 20 minutes into her process, when the woman had her tools on her desk, and the man approached her again. "This machine, in your genius, would of course have a mechanism to keep me from slipping and falling in this terrible weather," said the man.

And the woman obliged her new customer, and began redesigning the machine.

She created the oscillating shoe deflection matrix, the sock drying who-sly doo-sly, and the traction guidance confabulator. But the deflection matrix was causing the confabulator to misfire, and the confabulator was causing the who-sly doo-sly to go cold. The who-sly doo-sly was causing the matrix to stop oscillating.

Now the woman was getting irritated, and her design was beginning to look more like a ball of yarn, than a contraption, the likes of which she was known for. The contraption was doing so many things, each of which it was doing less than well.

On the due date, which was now several orders of time later than she had anticipated, she delivered the machine to the man. The bells rang, and the whistles whistled. The machine kept the shoes clean; the socks dry, and provided traction for the man.

The man saw the machine and was truly impressed by the gadget. However, he never used the machine because he got a pair of galoshes.

Moral: Don't let scope creep ruin your product, understand the problem and get the requirements up front.  Don't over-solve a problem for which there are already obvious solutions.