Henry Petroski has a 30 failure cycle for bridge technologies (see http://www.amazon.com/Success-through-Failure-Paradox-Design/dp/0691136424 http://www.amazon.

Henry Petroski has a 30 failure cycle for bridge technologies (see http://www.amazon.com/Success-through-Failure-Paradox-Design/dp/0691136424 http://www.amazon.com/Success-through-Failure-Paradox-Design... ).