Getting It Right Takes Time

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Our morning shower is a good example of a feedback system.  The dial setting on the tap is the input, the water temperature is the output, and the tap adjustment is the feedback.  We move the tap to hot, and by the time we find the soap, the water is scalding.  We quickly turn it down, only to find it's soon too cold.  Since there's a time lag between turning the tap and the results, we overreact, instead of waiting for the final outcome.

Overcompensation is common with feedback systems.  Economists are notorious for overcompensating, assuming the economy will respond more quickly than it often does.

When a response causes the input to increase, we call it positive feedback.  We experience it at a concert when we hear a piercing squeal from the sound system.  This occurs because the microphone, the input, is too close to the speakers, the output.  The sound magnifies as it travels from speaker to microphone and back through the speakers.  Getting it right needs space as well as time.

Positive feedback occurs in population growth.  If lilies on your pond, double the area they cover every day, and half cover the pond in 29 days, it will be completely covered in 30 days.  This shows the dramatic effect of exponential growth.

So next time you want to get it right, allow a time lag, and recognize that positive feedback can lead to exponential growth.