Have you ever looked at something and thought, "What a great idea! I want one!" but upon further consideration realize what a bad idea this thing actually is? That's kind of how I feel about doggy doors.
Of course, there are a lot of good things about doggy doors. They're a God-send for people who work through the day and can't let their dogs out. They're wonderful for people whose dogs like to go out in the middle of the night. And they're really great for people with a lot of dogs who don't want to get up 15 times a day.
However, there are a lot of issues with them. Assuming that you've installed the door correctly, and you don't have to worry about other creatures wandering into your house, there are three main issues I have with doggy doors. 1) They allow your dog to self reward. 2) They don't help with house breaking 3) You lose all sight of your dog's bowel movements. Let me explain.
They Allow Your Dog to Self Reward
This may sound a bit odd, but I like a lot of control in my house. There isn't necessarily a ton of order. Dogs play, there's hair everywhere, and there's almost always someone barking (I love it!). However, there is a lot of control. All the dogs know that they have to come to either me or Hans if they want anything, and this includes going outside. Outside time is something they earn for good behavior. Of course, they get to go out for potty time too, but even then I'm opening the door for them.
They Don't Help With House Breaking
When someone tells me their dog just won't learn to use the potty outside, there is one question I ask. Does he not understand to go outside, or are his signals that he needs to go outside not clear enough for you to pick up on? In most cases, the problem is that the owner doesn't realize the dog is asking to go out. The problem with doggy doors is that the dog never has to learn how to ask to go out. On top of that, the owner is never learning how to read the dog. This really isn't a problem unless you ever want to travel with or have someone else watch your dog. Imagine you're in a hotel room. Your dog has to go out, but has no idea how to ask, so he just stands by the door. You have no idea why he's standing by the door, and you figure he's just hearing and listening to the sounds of people passing. Eventually your dog will not be able to hold it anymore and will pee all over the carpet. Now imagine that instead of being in a hotel, you're in your in-laws house. Man, don't you feel awful?!
You Lose Sight of Your Dog's Bowel Movements
When your dog is sick, there are a few things the vet might ask. How much has your dog eaten? Is he drinking water? Has he used the bathroom? How did his stool look?
Can you answer all of these questions? You might (if you're lucky) be able to say you know he went outside, but can you answer whether he pooped at all. Can you say if it was normal? What color was the poop? Was there anything really unusual? Have you noticed worms?
I know it's all pretty gross to think about, but it's all really important when your dog is sick, and if something is that important, I want to have the answers. A doggy door doesn't really encourage me to do that.
Now then, I'm not completely against doggy doors, and I think they're great for some people. I do think there's a right way and a wrong way to use them. I don't think they should be open for your dog to go in and out all day and night. Some boundaries should be set.
Ideally, a doggy door would only be open when you're not home. It would be there so your dog could relieve himself during the long work day. It would also allow your dog to soak up some sun on the really pretty days (keep in mind, though, this also means your dog could track in mud on the rainy days). Once you got home, though, the doggy door would close. It would stay closed the rest of the night, and you would be the one letting your dog in and out.
This way, you have the best of both worlds. Your dog could have some freedom, and you wouldn't have to worry, but you'd also be able to exert some control, and you'd be able to answer all those important questions for your vet.
Basically, all I'm saying, is really think hard about the doggy door thing.