I've listed a few of the common misconceptions or errors-in-thinking about dogs that I've run into in my years as a pet dog trainer: The following bolded statements make me launch into a prepared speech which I've included for you below so that you too can have a speech to share with others when you hear these phrases. (But you might want to be more tactful than I am below sometimes!)
"My dog rolls on his back because he wants me to pet his belly. " This could be true, but it is also fairly common for a dog that is a little nervous to express this by rolling on his or her back in submission. If you think this may be the case, the best idea is to give your dog a little break from interaction.
"I don't feed my dog people food because I don't want him to beg." First, people food made of the same food as dog food is! Second, remember that you get the behavior that you reward. If you reward your dog for polite behavior, any begging will cease pretty quick. Plus, dogs that don't know any better will beg for people food even if you didn't give him any of that food because they can smell it! I do agree however that is a good idea to be careful about what you feed your dog, not to overfeed and not to feed unhealthy foods.
"I don't train my dog with treats because I want my dog to obey me even when I don't have any treats." Getting your dog to listen to you when no treat is in sight is a matter of practice and a little sneakiness. Your dog should never know for sure whether you have a treat or not but should always assume it's possible. For instance, I might ask my already trained dog to be sit and if he does, I can go to the cupboard and get him a treat. I don't need to have that treat in my hand and show it to him first, because he knows from experience that a treat is likely coming if he listens. This will come with practice with rewarding your dog for good behavior. It is also a matter of making sure you do not rely on showing your dog food in order to get him to behave. If you do not use treats or food to train your dog you will be missing out on a major way to reward your dog for good behavior and may instead have to rely on more negative interations to make your point. (which is not as fun!)
"My dog wants to go out of the doorway first (or pull on the leash) because he is dominant." Nah, he probably just is like all dogs and is for some reason really excited about going out of doorways. You just never know when there will be a squirrel on the other side I guess! It's a good idea though, to ask your dog to sit and wait to be released to go out of the doorway.
"It's a good idea to get two littermate puppies and raise them together so that they won't be lonely" In my experience, this generally backfires in a big way because you end up with twice as much puppy pee and poop to clean up and twice (or three times) as much puppy chewing and nipping and barking. Also, the two dogs can get so bonded they don't care about human company much or end up fighting because they become competitive with each other. One puppy at a time is definitely a good rule!
"My last puppy was not this difficult!" Everyone says this! I think we forget how difficult our previous dog was or if they were raised by our parents it definitely seems easy in retrospect.
"My puppy stays by me so I don't bother putting him on the leash when we are out." Puppies do stay close by naturally, but just wait until your dog is a bit older and look out! This is why young dogs should stay on the leash because we never know when they are going to get the wanderlust! And of course, start training your dog to come to you - it is never too early (well I guess you need to wait until they can walk!).
"My new dog doesn't bark at all" Famous last words! Most dogs don't begin barking until about 6 months and most adopted dogs have a honeymoon period of a couple of weeks in which they do not bark.
"I don't need to worry about socializing my young dog because he is always fine around people." Dogs don't tend to exhibit aggression until about age 1.5 years. Before that you will notice some small problems like shyness. Gentle socialization can help prevent this.
"My dog is always hungry so I feed him more." I've seen that this will lead to an overweight dog in almost all cases. Dogs seem to have been biologically designed to be ready to eat whenever food presents itself and keep eating until they pop (literally). It's a good idea to watch your dog's weight very carefully and adjust your dog's food intake as necessary to make sure you can feel your dog's ribs and that he or she keeps a "waist".
"I feed both of my dogs out of the same bowl because they get along well" Wow, what mellow dogs you have! Let's keep them that way and feed them out of separate bowls! Most dogs will eventually fight over food or eat too much or not get enough if fed out of a communal bowl.
"I crate my two dogs together because they get along well" I've seen that this can work for short periods for adult dogs that get along well, but for longer periods or younger dogs it is best to get a second crate so that they can both be comfortable and not have any arguments in a tight space.
I'm sure there are lots more. Want to add some? Add them in our comments box!