There is a fine difference between busy and effective. You can be busy with many different things and they don't have to be important or urgent or effective. It is fairly common to talk to our colleagues and friends as if a lot of work would equal a lot of important work but that is not necessarily the case. In order to be effective you have to know what you need to achieve and agree that the goal is important. This requires considerable time management skills since you have to say NO to many requests in order to achieve your critical goals.
Do you practice this on a day to day basis? For example at the beginning of a Project you might want to focus on the different stakeholders and their requests in order to understand what you team needs to achieve to be successful. Once you know that and the key stakeholders agree on a goal it is about execution. Note that this applies to traditional Project Management Methodologies as well as Agile Methodologies.
In any case once you have agreement on the Project objectives it is not the time to discuss rejected requirements over and over. It is important to know how the teams success is measured and then focus on these goals. It is your responsibility as a (Project) Manager to ensure the agreed upon goals are something your team bought into. Stop the busy work and focus on the important work.
