Just over two hundred years ago, Edward Rutledge signed the Declaration of Independence. His direct descendants are Goldie Hawn and Kate Hudson.
What sort of odds would you have been willing to lay on that bet? You could be standing at his deathbed in 1800, with complete and total knowledge of his genetic makeup and the society in which he lived, and the chances that you'd predict this outcome would certainly approach zero.
Just as the most trained geologists a million years ago (if there were any) could never have described the precise boundaries of the Grand Canyon today, and yes, just as the best investors can't predict with certainty what your next project is going to turn into.
We are now experts at the micro-physics of collisions, at predicting how a billiard ball will roll or how long it will take a penny to hit the ground if we drop it off the Empire State Building. Sometimes, we do a pretty good job of predicting how a sales call will turn out.
But add one or two or three hundred generations, and we're always (always) going to get it wrong.
Unpredictable isn't precisely the same as random. We can certainly make dumb choices, we can suffer from being unprepared, we can be the victim of bad judgment too. The essential thing to remember, though, is that every project is the work of a thousand generations, of decisions leading to decisions, of the unpredictable outcomes that come from human interactions. Given how unlikely it is that we'd predict Goldie Hawn, the best posture is obvious: Assume that your plans are wrong.
Expect that you'll be surprised.