What causes unemployment post-keynesianism?

involuntary employment

Explanation:

The Post-Keynesianism view is that effective demand is the main determinant of economic performance.

Thus, Keynesianism states that in an economy where there is a significant reduction in demand, it will affect the labor market which further leads to lower wages.

For example, an airline that has 100 workers is experiencing a sharp decline in demand (of flight bookings) because of a government lockdown may decide to cut down their staff capacity ad a result. leading to involuntary employment.

answer; comparing the additional benefits and costs;