Leash is a word that refers to a device for controlling a pet. Animals feel anxious and afraid when they are not allowed to move at will. This condition is called negative reinforcement and can negatively affect the animal's behavior.
A leash is part of training and an important element of controlling your pet's behavior. When an animal is trained to control a leash, it can help it learn to manage its motivation in other situations. If a dog is behaving in an undesirable manner due to a lack of autonomy or willpower, a leash can help establish a strong process for choosing between acceptable and unacceptable behavior. In particular, it can be used as a means of correcting unwanted behavior.
The concept of fetch training is to teach a dog to chase something that has the taste and smell of a human, but does not reward him for chasing. Dogs trained in these commands can chase and catch “game” simply because it smells and looks attractive to them, regardless of any consequences. They learn to race on command rather than on impulse.