"The worst of doing one's duty was that it apparently unfitted one for doing anything else"

This quote by Edith Wharton speaks to the concept that when one is so focused on fulfilling their commitments, they can become so consumed by it that it can prevent them from doing anything else. It indicates that when one is so concentrated on doing their duty, they can come to be so bewildered by it that it can prevent them from doing anything else. This can be seen as a warning to those that are so focused on satisfying their obligations that they forget to take care of themselves and their own needs. It is a pointer that while it is essential to satisfy one's tasks, it is also important to take some time for oneself and to make sure that a person is not sacrificing their own health and wellbeing at the same time.