Theory X is based on fairly negative view of human nature. It says that people are essentially lazy and uncomfortable with the idea of having too much responsibility for anything. They only turn up to work for the pay.
Employees have to be managed in a STRICT way, otherwise nothing will get done.
Theory Y, on the other hand, suggests people may be capable of something more positive - that they will seek of responsibility and try to get better at their jobs, from which they can get significant personal satusfaction. Theory Y managers have high expectations if their people. They are also much more likely to DEVELOP a truly motivated workforce.
-Douglas McGregor, a US psycologist at Market Leader 3rd English First