Once upon a time, I was working on a project at a high tech company in an LA suburb, and I was working for a manager that I'll call Mike (because that was his name).
Mike had once worked managing a group that put satellites in orbit, and from that experience he gathered some great wisdom, some of which he attempted to impart to me, and some smaller amount of which actually sunk into my young (at the time) head.
The most valuable thing I remember was that he always insisted we built what he called "golf course time" into his projects. It was calendar time (as opposed to time on task) for the folks working on the project to be doing something besides work (golfing, in his casef) and have that "Oh, wait, we didn't think about X" thought that can be the difference between a project going off the rails or coming in under budget.
We worked just as hard as the other groups, and got just as much done, but we would interleave tasks, so that everyone had some extra calendar time to come up with those effort-saving and project-saving ideas. And when someone did think of something, Mike would make a point of highlighting it, so that the rest of us would recognize those thoughts when we had them.
I don't always succeed in building extra calendar time into my projects these days, but I do occasionally come up with one of those ideas; for me it's usually while I'm reading, or working out.
More often though, I remember what Mike tried to teach me because I just got caught by surprise by a nasty little corner-case that I wouldn't have painted myself into - if only I'd managed to have had the time to have thought of it beforehand...