If the latest world record for the mile had the numerological significance of 3:30 or 3:31, it would have almost certainly been broken by now. Instead, it languishes at a maximally dull 3:43.
I've often thought about the arbitrary cutoff points we set for goals, and how those magic numbers make a huge difference in the importance we place on them. Very few people set a target like saving $49,220 for their kid's first two years of college. The milestone approach is a nearly-universal way of deceiving ourselves. It probably comes at a measurable cost in GDP.