“Science is about knowing; engineering is about doing.” — Henry Petroski

The paradox is that when we model future designs on past successes, we are inviting failure down the line; when we take into account past failures and anticipate potential new ways in which failure can occur, we are more likely to produce successful designs.

I emphasize that virtually every engineering calculation is ultimately a failure calculation, because without a failure criterion against which to measure the calculated result, it is a meaningless number.

Many of the familiar little things that we use every day have typically evolved over a period of time to a state of familiarity. They balance form and function, elegance and economy, success and failure in ways that are not only acceptable, but also admirable.

Engineering is achieving function while avoiding failure.