I think we are partially to blame for the frantic hurry-hurry-hurry culture where we work. Many of us cannot deal with the feeling of things left undone, making us anxious. To alleviate the feeling we bundle it up as the next action for someone else and throw it over the fence in the form of an email. Then it is no longer our problem; the discomfort is gone, but someone else has to deal with it and they have the same problem. It is like the worst game of hot potato, at the end of the day we all try to have the least amount of tasks left undone.
First, we need to realize that we will never completely get rid of this feeling of things left undone and we have to get comfortable with that. Next, we need to apply a task management system so we can leave less important tasks undone at the end of the day and allow us to focus on the more impactful work.