It's simple statistics. The chance of every parameter not being an outlier is small. https://www.thestar.com/news/insight/2016/01/16/when-us-air-force-discover

It's simple statistics. The chance of every parameter not being an outlier is small. https://www.thestar.com/news/insight/2016/01/16/when-us-air-force-discovered-the-flaw-of-averages.html https://www.thestar.com/news/insight/2016/01/16/when-us-air-... "Even more surprising, when Daniels averaged all his data, the average hand did not resemble any individual’s measurements. There was no such thing as an average hand size."