“Numbers don’t lie” is, well, a lie. Plenty of stats, perhaps even the bulk of what’s out there, don’t properly reflect reality. When you hear that the Cowboys have a gaudy record when they rush the ball X times or they struggle when Tony Romo
has Y attempts, those numbers are misleading because they’re simply correlated and not the result of any sort of causation. There are many statistical relationships out there that aren’t actually rooted in reality. There’s a pretty strong relationship between shoe size and yearly salary, for example, but we’d never argue that people make more money because
they have big feet.
It can be difficult to determine which stats are truly meaningful, i.e. the ones that don’t “lie.” The ultimate goal of any stat, in addition to explaining a past event, should be to predict the future. When numbers are utilized to make accurate prognostications, we know they’re “good” (useful) stats. That’s one reason that passing efficiency is far better than, say, rushing attempts when we’re determining the quality of a team. Rushing attempts can explain past success, but they can’t accurately predict future victories. Meanwhile, passing yards-per-attempt is perhaps the top individual stat for predicting future team success.