I've read on some sites that dogs lean on you because they feel comfortable with you. Other sites say that it is a sign of dominance. So, is it good or bad?
The issue of the reason for dogs leaning on owners is quite conflicting. As you said, some people believe that it is a sign of dominance but from personal experience and some research, I believe your dog will lean on you for affection, to get your attention .
My dog leans on me mostly when he wants something. Like, to play fetch, remind me it is time for me to feed him, etc. This absolutely is not dominance, he is just trying to get my attention.
But not a single person brought up the fact that many dogs will lean on their owners for security. They will lean on their owners because they are shy, fearful or insecure. They are not trying to dominate their owners. They are trying to feel safe.
Nine times out of 10, when dogs lean on us they really are just seeking attention.
Shy dogs might lean on their owners for security.
The best way to react to this is not to pet the dog because this will not build his confidence rather it will make him more timid and shy.
It’s easy to nurture a small dog’s fear by carrying him around and telling him “It’s OK. It’s OK, baby.” But this will not help the dog build any confidence.
Instead, the owner should place the dog on the ground and slowly help him understand that nothing bad happens in new situations. The owner should ignore the dog or move away when he frantically paws at her legs to get back up. She should give him a treat or pick him up only when he is calm or if the situation is truly unsafe for the little guy.
I'll say is not bad for your dog to lean on you as long as you understand your dog so as to take the appropriate actions. When your dog is leaning for affection, It is best to pet him and show the affection he wants but when your dog is leaning for security or because he is scared, It is better to help him build up his confidence.
Personally I think dogs can detect when people are sad or down in the dumps, I've had a number of different owner's dogs walk up beside me and lean. Some I never met prior. Once at a party with a number of people wondering about, out of nowhere, dog walks up beside me, sits, leans and the dog's owner told me later he never did it prior.
I believe it is a sign of affection and they lean because they like who they lean on. I have two dogs and they often will come to me and lean together to get petted or a back scratch. One thing that makes dogs really feel good is to rub their backs from the back of the head to the tail, something like a massage. It makes them feel good and seems to relieve stress that builds up from their ability to hear and feel things going on around the area that we can't seem to hear or feel.