An extremely important factor when you're training your dog is how consistent you are being.
This might seem like an obvious statement, but it's often overlooked. I've trained hundreds of dogs and during that training, I've also trained all their owners. I often see people overlooking this as an important factor when it comes to training a dog.
"Consistency is everything. If you're consistent with enforcing cues and backing up what you say then that consistency will be matched with reliability."
Once you're sure that you taught a behavior in the best way possible and that your dog understands it, your consistency will determine how reliable that behavior becomes. You also need to make sure that you are motivating your dog to want to do the behavior.
Remember that no behaviors become reliable overnight. Every behavior needs two things; Understanding and Motivation. Once you make sure your dog understands what you want and they are motivated to do it then you should be consistently enforcing the behavior when they choose not to do it.
How to Enforce Behaviors
By enforcing the behavior, I just mean that you should give the cue one time and if your dog does not respond within two seconds you should go put them into that position. This should be done gently and calmly. You want to try to avoid repeating a cue that does not inhibit a behavior. So if you're asking your dog to do something like sit, which requires them to act then the cue should only be said one time. For example, If you say 'sit', 'down', or 'come' and your dog chooses to ignore you, repeating the cue will only reinforce the fact that your dog does not have to listen when you speak. By going and enforcing the behavior you asked them to do, you are showing your dog that they will have to respond or you will always back up what you say. This means that when you're teaching a new behavior, the cue for that behavior should only be given when you are able and willing to back it up. If you are carrying groceries into the house and your dog is not very reliable with listening to a cue yet, then you should not give that cue. You cannot back up what you say when your hands are full unless you are willing to drop the bags if your dog does not respond. This is a very simple concept, but it's not easy in practice. We tend to want everything right away. So we quickly start telling our dogs to do things that either they don't fully understand or have not been conditioned enough yet.
If you can refrain from using a cue outside of training drills for the first few weeks, your dog will learn the behavior faster and the behavior will become reliable much more quickly. But if you are constantly giving a cue that you are not able or willing to back up, then you will get inconsistency in your dog's reliability with that behavior. There is really no reason to give a cue that is unreliable. Saying 'sit' knowing that there is a good chance your dog will not listen is most likely just a bad habit. It's not practical to say a cue when the chance of your dog responding is very low. Breaking a habit can take some time, so don't get frustrated if you catch yourself doing this. If you are self-aware enough to know you're doing it, then you will break the habit.
"Dog Training is about being Patient, Consistent, Empathetic, and Motivating!"