When Averages Hide the Truth

Averages are the biggest liars in statistics. A bank once decided their customer service

calls were taking too long, so they penalized employees for high average call times.

On paper, it worked perfectly. The average time dropped like a rock. But then a data

analyst actually plotted the graph and saw something weird. There was a massive

spike of calls lasting less than ten seconds. Turns out, employees were just picking up and immediately

hanging up on customers to game the system. The math was right, but the reality was a disaster.

Always check the shape of the data, not just the number.