what are the lessons learned from Hawthrone experiments?

Answer 1

The major lesson is that we should not tell people when we are studying them. While the study was in process, productivity increased. When the study ended, normal expectations returned.

The researchers also found that, in the bank wiring room, workers tended to set their own expectations as to productivity. People who didn't live up to the standard were called slouchers; and people who performed above the level were known as rate-busters.