"Theory X" ' "Theory Y" or "Theory XY" ? to what Extend combinations needed?

Simply mutations of concepts are not acceptable or proves to be very hard to implement. So the mergers of concepts are based on the situations which are opreational and there is no limit to be scheduled for any particular.

I think this depends on the working situations prevailing.

What you say ?

Theory X

In this theory, management assumes employees are inherently lazy and will avoid work if they can and that they inherently dislike work.

Theory Y

In this theory, management assumes employees may be ambitious and self-motivated and exercise self-control. It is believed that employees enjoy their mental and physical work duties.

 Theory X and Theory Y combined

McGregor had identified Theory X and Theory Y differently for the basic characteristics stated previously in the above sections of what these theories represent. Theory X assumptions are that individuals dislike their careers. Theory X people have to be supervised. As for Theory Y assumptions are that individuals like their careers and are willing to take part in responsibility. Theory Y people don't need supervision and can be expected to turn good productive value in their jobs.

The people in  Theory X and Theory Y are different sets of people.

The motivation method depends on the:

1- Type of environment

2- Type of task

3- Type of performance

4- type of person

So, we can apply theory X in specific situation, Theory Y in second situation, and XY in a third one.

Theory Z, which is provided by Willium Ochie.