According to you, under which conditions can a grievance arise?

According to you, under which conditions can a grievance arise?

Grievance may result from various conditions. Following are the few factors:
-Dissatisfaction of pay & incentives.
-Unhealthy & unsafe working conditions.
-Unplanned management decisions such as demotion, change in the job profile, transfers, etc.
-Mental or physical harassment from seniors or colleagues.
-Violation of law or Company rules.
-Violation of contractual agreements.