Final answer:
The unit manager's initial error in addressing the evening staff's poor morale was incorrect problem identification, failing to recognize that the primary concern was with the team leader and patient assignments, not scheduling.
Step-by-step explanation:
The unit manager's first missed step in problem solving was incorrect problem identification. Before taking any action, it is critical that a manager accurately identifies the root cause of a problem. In this case, the manager assumed that poor morale was due to the need for time off and scheduled holidays without consulting the staff. However, the real issue presented by the staff nurses was related to the team leader and how patient assignments were being handled. The manager failed to engage in effective communication and did not seek to understand the staff's perspective prior to making a decision. It's essential for managers to correctly identify problems and consider the input of their team before implementing solutions.