For an ill-trained dog who wont come when called or gets into scrapes with other dogs or people when off leash, a retractable leash may seem the perfect solution. It allows an unruly pet more freedom than a regular leash as the line unfurls - 10, 15, or more feet. But an untrained pet is the very dog for whom a retractable leash is a bad idea. Thats because it doesnt take the place of responsible training that teaches dogs to come wait, and leave it. So dogs on retractable leashes continue to lunge, pull, and engage in all kinds of other undesirable behaviors, just as they do on short leashes, but the leashs lock mechanism doesnt let them be reeled in fast enough to contain the havoc. You have to walk toward the dog to shorten the leash, which takes time.