Personal development is a processfor people to assess their skills and qualities, consider their aims in life.
Personal development is an ultimate necessity: "The extent to which people are able to develop depends on certain needs being met and these needs form a hierarchy. Only when one level of need is satisfied can a higher one be developed". You can also consult Abrahma Maslow's Hierarchy Needs to deep in its importance.
Reference: 2011-2019, (c) Copyright SkillsYouNeed.com. “What Is Personal Development?” SkillsYouNeed, 2017
Personal development is developement such as character building. it is important because it shapes the mindset of an entire generation which would ultimately impact society, either good or bad
The servants do not "abscond" because Montresor tells them to stay at home; they do so because he tells them he will be gone all night. They don't care if he finds out that they all left to join in the carnival. He can't fire them because he can't get anybody to replace them.