In my experience, being 85% prepared is a great place to begin your battle. We are never 100% prepared for anything. 100% percent preparedness implies that you “know” all outcomes and possibilities. We don not. Variables are at times, infinite. The best we can do is analyze and anticipate based on past actions, point and subject references, and experiences. You will never be 100% percent prepared for anything.
To me, 85% is the sweet spot.
Enough to confidently set out on a course of action. The 15% percent is where we flourish and grow. Unforeseen circumstances, variants of what you anticipated and shocking twists all imbue us with knowledge and experiences that we wouldn’t or could never come up with ourselves. So, we set out to slay the dragon, armored and weaponed down, only to discover we’re fighting something else entirely.
Set out anyway. Pivot when necessary. Finish the task.