How should the collar feel once properly applied on the dog?

When a collar is properly applied on a dog, it should be snug with no excess slack. This ensures that the collar is secure enough to prevent it from slipping off or being easily removed by the dog. A snug collar also prevents the risk of injury or escapes, as a loose collar could become a safety hazard, allowing the dog to get caught on objects or enabling it to back out of the collar.

While comfort is important, the primary goal is to maintain an appropriate fit that allows the handler to maintain control of the dog. Therefore, a snug fit means that the collar allows for some movement but is not so tight that it causes discomfort or restricts breathing. This balance is vital for the safe and effective use of a collar during walks and other activities.