Can your dog be left alone with difficulty or not at all, does he behave aggressively towards you or other dogs, does he destroy all your furniture? In other words, Rambo gets out of control? Then it might be possible that you have a so-called “problem dog” at home.
What is the definition of a “problem dog”?
The term “problem dog” was chosen somewhat unfortunate. On the one hand, the term suggests a certain character trait of the dog, a condition independent of humans, which is not irreversible. In this point it would probably be better to ask about the problem and not to call the dog in general a problem.
On the other hand, a problem is always in the eye of the beholder. An example: The dog jumps at his owner when greeting him, some people don’t mind that at all and even find this behaviour cute and welcome. Some others find this behavior impossible and problematic.
If you speak of a so-called problem dog, you usually means a specific behavior, which is problematic, whereby as already mentioned “problematic” should always be interpreted subjectively. It is therefore a dog with a “problem behavior”.
Born to be a problem dog?
Clearly, the answer is no. No dog is born to be a problem dog. That would mean that the behavior must have purely biological, genetic causes. However, there are dogs that have less good conditions for the start into life than others. Unfavorable living conditions as well as inexperience or disinterest on the part of the owners, favour certain unwanted behaviour patterns and let the dog quasi “mutate to a problem dog”.
Dogs always want to “please” us and their behavior what they show is from their point of view suitable for the respective trigger. Often we unconsciously reinforce the dog’s behavior or even trigger it.
The problem is usually at the other end of the leash
Let’s take the situation shown above again: Dog jumps at his owner during the greeting. Why does he do this? In order to find out the cause, as with any other problematic behavior (aggression on the leash, defense of resources, uncleanliness, etc.), you first have to think about the emotion the dog is doing it from. From joy? What does his human dogmum or dad then do, for example, petting?
If the dog is stroked in this moment, he gets attention, a reward for his behavior. The (undesirable) behavior is intensified (positive conditioning). Under the link How dogs learn, you can read more about this.

What can I do myself?
Consistency in your own behavior: It is advisable to take a closer look at the history of your dog’s behavior. Did you like it when your dog jumped at you when he was a puppy and now it bothers you? Then you shouldn’t be surprised if your faithful friend shows this behavior as an adult.
The be-all and end-all is regularity in your own behavior. If you are hardly consistent, it is even more difficult to get rid of the problem, because the respective behavior of the dog always leads to success or is self-rewarding (barking). Clear rules are very helpful.
Avoid stress: Stress favors problematic behavior, since our dogs have difficulty thinking clearly under the influence of stress hormones. Therefore, get to know your own dog well and pay attention to your dog’s individual stress characteristics (calming signals, skipping actions). A stress indicator would be, for example, if your dog, who otherwise likes to eat treats, cannot/does not want to accept them or if he does not carry out signals which he actually controls very well.
Clear Language: Unfortunately our dogs speak a different language than we do. Therefore it is important to establish a clear communication in word/sound and body language. You should be as predictable as possible for your dog and tell him clearly what you want.
A busy dog is a balanced one: Dogs have different needs that need to be satisfied regularly. Pay attention to how much physical and mental workload your dog needs and which needs are not satisfied.
The Training
With regard to training, “problem dogs” are always trained by a single person or a second trainer is consulted, depending on the problem. Slowly and steadily the problem behaviour is worked on by means of positive reinforcement.
By means of so-called management measures (leash up when you are welcomed, don’t leave anything lying around when there are resource problems, muzzle training, box training, etc.) the everyday life with your faithful friend is trained and mastered.
If you have the feeling that a problematic behavior is developing which you can’t control anymore, don’t wait too long and get a competent advice. You can find a qualified dog trainer here.
It is always easier to nip a “problem behavior” in the beginning than if it has a months- or mostly even year-long history. It is even more difficult if the behavior is always successful or self-rewarding.

Summary
The term problem dog always refers to a certain undesirable behavior of the dog. In no way is it born that way, rather the causes lie in the social environment of the dog and are partly brought up by us humans, partly also unwillingly. But no reason to panic, with targeted training and a little patience the dog can learn what is desired from him.