A problem with hindsight is that it's biased: looking back from the vantage point of hindsight, we tend to think that things were more predictable at the time than they actually were.
A related problem is that we tend to not handle 'counterfactuals' well: we may miss how easily things could have turned out differently than we would predict from the vantage point of hindsight, due to the sometimes large effects of minor differences in circumstances, good and bad luck, etc.
So I would argue that the 20/20 appearance of hindsight is somewhat illusory, and we need to be careful about trying to draw specific lessons from hindsight. We can probably draw some general lessons from hindsight, but the same lessons may be more efficiently and effectively learned by looking at the collective experiences of our colleagues: what did they do and not do, and how did things work out for them?
I very much agree with James' point about trying to have a sense of how much we don't know. This applies to engineers at all stages of their careers. For younger engineers, the issue is largely a matter of not knowing things due to inexperience. For more experienced engineers, the knowledge they do have can sometimes foster a degree of overconfidence, which can contribute to underestimating how much they don't know. In my career of three decades so far, the best engineers I've known have all been humble, incisive, and always trying to learn more.
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Irfan A. Alvi, P.E., M.ASCE
President & Chief Engineer
Alvi Associates, Inc.
Towson, Maryland
www.alviassociates.comialvi@...------------------------------