There are probably as many answers to that question as there are children. 

To say that one particular factor is the sole cause of misbehavior would be misguided and highly inaccurate. There are a number of biological, psychological, and environmental factors that work together to influence a child's potential for misbehavior. Here are some examples: 

Biological Factors: Psychological Factors: Environmental Factors: 
Temperament 
Genetics 
Chemical Imbalance 
Brain Disorder 
Developmental Disorder Trauma 
Ineffective Coping Skills 
Psychological Disorders 
Low Self-Esteem Diet/Nutrition 
Poor Role-Models 
Exposure to Violence 
Ineffective Parenting 
Media Influences 
Peer Pressure 

Now that we have listed at some of the influences of misbehavior, let's look at the two biggest motivations of misbehavior: ATTENTION and POWER/CONTROL 

Attention: 

For many children, negative attention is better than no attention at all. If your child appears to be acting out with the purpose of gaining attention, then the solution is simple: GIVE YOUR CHILD MORE ATTENTION (but do so when he or she is behaving appropriately). 

* Acknowledge your child when he or she is being positive. 

* Get to know your child by spending more time talking and asking non-intrusive questions. 

* Devote a segment of time each day to spend quality time together. 

* Ignore behaviors that are meant to annoy - such as whining, mocking, complaining, begging, pouting, etc. 

Power/Control: 

Many negative behaviors are brought about by the need to exert power and/or control over others. Some of the more common behaviors of children motivated by power and control are: dawdling, picky eating, bossiness, always having to be "first," passive-aggressiveness, threatening, engaging in power struggles, etc. These children will typically respond better when given choices rather than demands. Choices allow children to "control" what happens. 

Gaining insight into the influences and/or motivations of your child's misbehavior will certainly help you to better handle these behaviors as you are confronted with them. Start by minimizing the negative environmental factors in your child's life as much as you can. Next, consider having your child assessed for biological and/ or psychological problems. Remember to keep the lines of communication open and take the time that is needed to care for yourself. Help is only a phone call or support group away! 

About The Author
Chris Theisen is the author of The Parent Coach Plan located at his website: http://www.parentcoachplan.com