The Pareto Principle, also known as the 80/20 rule, states that 80% of effects come from 20% of causes.
The closer we get to a goal, the harder we try.
A cognitive bias that causes us to rely too heavily on the first piece of information we are given about a topic.
An economic principle stating that as an investment in a particular area increases, the rate of profit from that investment, after a certain point, cannot continue to increase if other variables remain a constant. As investment continues past that point, the rate of return begins to decrease.
When a measure becomes a target, it ceases to be a good measure.