Always ask for the value to be provided by a requested capability.
Very often customers and end-users state what they think is a viable solution on a problem as a requirement. The classical story on this was first told by Harry Hillaker, the lead designer of the F-16 Falcon. His team was requested to design a Mac 2 - 2.5 aircraft,which is a non trivial task to do.
When the design team asked the air force why they needed Mac 2, they was told that Mac 2 was required to escape from combat. When the real need was articulated the design team was able to provide a good solution, by combining aircraft agility with an high thrust-weight ratio, providing high acceleration, not maximum speed.
This lesson should be brought into software development as well. By asking for the value to be provided by a requested feature or requirement. By understanding the value and real need the designers are able address the real problem, and hopefully in the end provide a more elegant, better and hopefully cheaper solution compared to addressing the stated need in a head on approach.
By Einar Landre
This work is licensed under a Creative Commons Attribution 3
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