MINE PLAN VS EXECUTION!!

There are some mines out there that beautifully execute on the mine design, and especially on the mine schedule. I get goose bumps if I go to the lookout point and the actual mine is a mirror image of the mine on plan. Difficult to accomplish and maintain, but so worth the effort. And then you get mines where the execution is the complete opposite of the mine plan, and sometimes with good reason. So why do some mines get it right, and others don't? Is it technology, or maybe budgets, or leadership? Or all of it? Your thoughts on this hot topic are welcomed!