Book excerpt: This may seem self-explanatory, but it's helpful to work through this question thoughtfully. Is self-control really that important, or is it better to enjoy the moment and not concern oneself with future outcomes? Besides risking the ability to achieve long-term goals, there are other problematic issues with a lack of self-control. People who lack self-control often give in to impulsive behavior and emotions as well. This means that they may make poor choices that harm themselves or others and react poorly when they don't get what they want. Imagine a toddler who wants something but the parent says no. Often, the initial reaction is to behave impulsively. They may throw a tantrum and hit and scream. Toddlers are still learning to regulate their emotions and respond appropriately when things don't go their way.A person who lacks self-control may be an unstable person, prone to fits of anger and unethical decisions. There's more at stake to a lack of self-control than a forgotten New Year's Resolution--it may mean the difference between a person who is successful in personal relationships and careers, and one who is not.