The answer to this question is implied by the wording of the question itself. The question asks about our “highly litigious society.” The fact that our society is litigious is relevant to this question because a firm that does not manage its dismissals properly is likely to find itself being sued for one or another reason.
In effect, in the United States today, it is important to have behavior-related reasons to dismiss an employee and it is important to document those reasons. This is important because we have many kinds of anti-discrimination law. If a firm fires an employee without being able to clearly document that employee’s poor behavior (with lack of productivity counting as poor behavior in this context) it opens itself up to claims that it is firing the employee for some forbidden reason. For example, it might seem that the firm is firing the employee because they are too old. Because there are many reasons that are not valid for dismissing an employee, it is important to document the reasons why a firm is thinking of dismissing a person and it is important to document that the employee has been given chances to reform.
Thus, it is important to manage dismissals properly so as to avoid the prospect of lawsuits.