In The Human Side of Enterprise,Douglas outline two opposing theories of work and motivation.
What he calls Theory X is the traditional approach to works and working which assumes that people are lazy and dislike work,
and that they have to be both threatened(for example,with losing their job) and rewarded.it assumes that most people are incapable of taking responsibility for themselves and have to be looked after. Theory Y, on the contrary,assumes that people have a psychological need to work and want achievement an responsibility.