Firing someone is required but not always necessary. It’s an easy way out.
Managers fire people because they disagree with them. Instead of letting people go, they should be open to criticism and different opinions. Creativity is the byproduct of tensions and multiple perspectives.
Lack of alignment is a consequence of the above. Managers fire people because they are not aligned. Organizational alignment is a myth, as I wrote here on Medium, that managers need to let go off.
Lack of performance is another common reason why people end being fired. In many cases it can be fixed. Are you training the person to do the job? Is she/ he in the right role? How’s the manager helping develop skills -both soft and hard- and providing opportunities?
When people are not motivated, they underperform. And they get fired for either being demotivated or for underperforming. Motivation is a 50/50 responsibility. Employees to do their part by finding pleasure on what they do and doing their best work. Managers need to provide challenges that make people excited rather than telling him how to do their work or assigning tasks rather than purpose-driven goals (not just metrics).
Politics is another common reason why people get fired. Everyone contributes to a political environment. But leaders are the only ones who can reduce politics by being fair and providing a safety and transparent environment. Their behavior should not only discourage politics but also punish those who prioritize politics over doing great work.
The strongest reason to fire someone is when they putting workplace safety at risk. Either because they are playing politics or behaving as “asholes” as Bob Sutton writes.
Regardless if they are managers or regular staff, those who turn the workplace into an unhealthy place should be fired.