Every superior has the ability to make or break the career of their subordinates by virtue of the administrative powers vested in them and the positional advantage of being superior in the organizational hierarchy. A manager's primary responsibility is to get things done through the subordinate employees and not to offer explanations for their lapses and failures. A consistently inefficient employee would be a dead weight, and as such, their continuation in the organization cannot be tolerated by any prudent manager. Instead of dismissing an incorrigible employee on disciplinary grounds, management may sometimes ask such an employee to resign under some pretext or another. So, always remember, there is no smoke without fire. Take time for self-introspection. However, my above observation does not imply that all managers are aboveboard. If you have sufficient and strong evidence to prove that the allegations against you are false and fabricated, you can fight back instead of meekly resigning. It depends.
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