Matthew Swyers wrote an excellent piece for Inc. today about why ultimatums don't work in employer-employee relationships, but all I could think about was how proactive management would eliminate the need for an ultimatum in the first place.
Proactive management requires that leaders clearly express expectations -- of an employee's conduct, work performance, project communication, and so on -- and, you know, manage how the team rises to the occasion. Lackluster and stellar employees alike stand out like sore thumbs in this paradigm.
Tough conversations suddenly become easier with proactive management. Instead of in-depth counseling sessions, where many managers may issue ultimatums without knowing it, the manager's conversation is simple: You knew our expectations for your performance and did not meet them. Is this due to a lack of preparation or a lack of effort? The former is a situation you can address with training, while the latter indicates a poor fit with the company.