Are Bosses Afraid To Terminate Incompetent Workers?

I have a question to people in management or leadership positions. Why do companies keep incompetent workers? Workers who make mistakes and learn from them and get better are the keepers. Workers who are incompetent are the garbage workers. If these garbage workers create an stressful work environment such that the garbage worker is not a team player, a worker who fails to innovate, a worker who has attitude problems, a worker who makes too many mistakes and fails to learn from them, then why are these workers still employed?

I fail to understand why companies keep the ineffective workers on their payroll. Why? Anyone know the reason? In the meantime, fire the incompetent workers. Get rid of them. In the short term, a department is going to be behind. There is a chance in the long run the replacement worker is the key worker for the department, the innovator who makes things happen, the new worker who solves problems. Have the courage to terminate incompetence. Mistakes are acceptable. Incompetence is unacceptable.