Another month, another rationality quotes thread. The rules are:
Please post all quotes separately, so that they can be upvoted or downvoted separately. (If they are strongly related, reply to your own comments. If strongly ordered, then go ahead and post them together.)
Do not quote yourself.
Do not quote from Less Wrong itself, HPMoR, Eliezer Yudkowsky, or Robin Hanson. If you'd like to revive an old quote from one of those sources, please do so here.
No more than 5 quotes per person per monthly thread, please.
Provide sufficient information (URL, title, date, page number, etc.) to enable a reader to find the place where you read the quote, or its original source if available. Do not quote with only a name.
This is a common failure mode, where the risk analysis is ignored completely. Falling in love with a perfect plan happens all the time in industry. Premortem analysis was not a thing back then, and is exceedingly rare still.
Another month, another rationality quotes thread. The rules are: