In the end, the manager should take responsibility. It's quite easy for a competent manager to identify poor service, and if it's not addressed, it can harm the company's reputation. If an employee consistently provides subpar service to customers, and the manager is unaware of it, then they're not fulfilling their role. There could be various reasons for subpar service, such as a demotivated employee or personal grievances, but it's the manager's duty to address these issues and, if necessary, terminate the employee.

Sometimes, bad service can be due to customers having unrealistic expectations. They might expect more than what’s actually offered. Also, miscommunication from the customer's end can lead to misunderstandings, resulting in service that seems bad but isn’t really the company's fault.

Bad service is often a joint responsibility. It's not just about the service provider; customers also play a role. Good communication and feedback from both sides are key. Plus, everyone in the company, from employees to stakeholders, needs to work together to improve service.