Psychology must be based on facts, not hypotheses.

It always seems impossible until it's done.

The best solutions often come from listening to those who work on the water every day.

丰田模式的关键及其独特之处不在于任何单一要素，而在于将所有要素整合为一个系统。必须每天以非常一致的方式实践，而非断断续续。