When we think about "correcting" a dog, the thought process behind this is to let the dog know they are in the wrong. The problem with this approach is that often the behaviour the human doesn't like doesn't have the same motivations behind why it's happening that it would for a human.
First let's talk about what a "correction" typically looks like:
Frank is out walking his German Shepherd named Molly around the neighbourhood, on leash. As they turn the corner, a stranger carrying a stack of boxes wearing a ball cap and dark glasses is right in front of them. Molly barks. Loudly. Frank, who is embarrassed, jerks Molly's leash and says "no!".
Here is a break down of Molly's behaviour, and the motivation behind it;
Molly is a German Shepherd, bred to guard
Being startled by strange looking people often results in a fear response such as barking
When an animal is on-leash they are naturally more defensive
Barking is communication, it's not "bad" behaviour, humans just may not like it but they were bred to vocalize, alert and warn
Frank didn't like the barking, but based on the above break down, was it fair for him to get upset?
Corrections; what are they?
A "correction" is the attempt to let an animal know they shouldn't do what they are doing. I do NOT recommend any of these and we will go over why shortly.
It could be:
a leash pop
a stern "no"
jabbing the dog
squirting with water
alpha rolling
tapping the dog on the nose
clamping their mouth shut
using the "tssssst!" sound
"ah ah!"
What "corrections" really do
When we look at Franks story with his dog Molly, his intention is short-sighted. He is getting upset with natural, instinctual behavior, and his dog won't understand WHY. Molly just knows that her person is angry. With repeated "corrections" Molly just starts to fear Frank and her behavior is apathetic. She starts to fear men in general. The side effects are like ripples in a pond. You won't see them until it's too late.
We also see that dogs that are "corrected" for one behavior may use another behavior to achieve the same result... and often times it is an escalated version. So, now Molly may not bark at all when she is frightened or startled, she may go straight to a BITE.
What "corrections" don't achieve
Suppressing behavior does not teach our companion animals a better option. Isn't it only fair that we do? Some examples of better options instead of corrections:
using a "let's go" to gain space if our dog barks on leash
proactively engaging more and rewarding more on walks
using the Engage-Disengage protocol for leash reactivity
anticipating our dog may jump on guests entering the home and setting up a baby gate to give our dog space from guests because he is excited
"If I don't correct behavior don't they think it's ok?"
As I mentioned earlier, animal behavior is not the same as human behavior so your dog is likely not behaving in a certain way because they are trying to be naughty. And even if that was the case, we still aren't teaching our dogs what is more desirable AND being fair to them. We also are going to see negative side effects with the "no" approach.
We can't reason with dogs. They are amoral beings! The don't understand right and wrong, good and bad. The only way you'll make the behaviour worse is by continuing on the path of corrections and punishment.