Lack of Training
Some dogs are simply laid back and do not require a lot of formal training. However, there are also some dogs that will benefit from formal training so they learn what behaviors are desirable and what behaviors will cause them to get into trouble. If your dog is misbehaving constantly, look into hiring a professional trainer who will work with you and your dog one-on-one.
Lack of Exercise or Boredom
There are certain breeds that are classified as high energy. These breeds will require an intensive exercise program or they will begin misbehaving because they do not know what to do with themselves. Herding breeds do require a lot more exercise as do Terrier breeds. Research your breed and know what the exercise requirements are for your breed. Dogs that suffer from boredom will misbehave, not because they are willful or stubborn, but because they do not know what to do with themselves. Provide plenty of room to run and play and also invest in some interactive toys for your dog to provide stimulation and reduce their boredom.
Reinforcing Bad Behavior
When your dog misbehaves, many times you will unknowingly reinforce that behavior by rewarding them. A dog that barks for attention and receives attention, either in the form of petting or even yelling, has just been rewarded for that behavior. Dogs are smart animals and will learn how to behave to get what they want. If you do not want your dog to bark, do not encourage it and do not give them the desired attention they are seeking.
Unfamiliar with Breed Characteristics
Many times a dog owner will bring home a dog because they are cute or they had sad eyes. But, that new dog owner probably did not research the breed before taking on the responsibility of the new dog. Toy dogs are harder to housetrain, herding dogs are more likely to chase, working dogs can become more aggressive, and each breed has their own special idiosyncrasies that makes them unique.
Unfamiliar with Adolescent Dog Behavior
People do not necessarily understand that dogs go through an adolescent phase, similar to the teenage phase that people go through. Generally, dogs will go through their adolescent phase between 5 months and 18 months of age. During this time, your dog will test their limits and see what they can get away with. You will notice that your dog is misbehaving more often than usual and you have to stay consistent in your training.
Canine Anxiety
A dog who is anxious, perhaps due to separation or a phobia, may misbehave or act in a destructive manner. This may not be an intentional act. Punishment is not the answer; the reason for the anxiety or stress needs to be addressed.