What explains a lack of self control?

People do all kinds of things that are bad for them. They eat salty, fatty foods. They smoke. They engage in risky behavior in so many different ways. Some people know the risks they are taking, and they don’t change their behavior. Some say they can’t control themselves.

One view is that these people are hedonistic. Another is a lack of empathy (for when their behavior hurts others). Often people are very judgmental about those who claim to have no self control.

Some people seem to have no problem controlling their pleasure-seeking behavior. They might look down on those who don’t control themselves. And they don’t believe it for a second when a person claims they can’t stop themselves.

What do you think is going on inside of people who seem to lack self control? Is there some reason why they do this, or are they just lazy, hedonistic, uncaring people? If there is a reason, how can they overcome these selfish desires? Can they learn, or should they just be dismissed as cheaters and self-indulgent failures?