|A retractable leash|
They're Comparatively Expensive and They Break EasilyAlmost all retractable leashes are twice the price of a standard leash of a comparable weight class (i.e. the strength needed for a dog of a certain weight). This isn't surprising as they're significantly more complicated, with multiple moving parts, while a standard leash in its simplest form only needs sewing or riveting in two places. One major consequence of this increase in complexity is the risk of one of the moving parts failing and rendering the "retractable" part of a retractable leash nonfunctional. There have been more that a few instances of retractable leashes failing very shortly after purchase. In comparison, unless your dog has a penchant for chewing whatever is attached to its neck, a standard leash can last decades before needing to be replaced from wear.
As a Training Tool, They are Virtually UselessDon't get me wrong, there are very specific scenarios when a retractable lead would be useful. However, it should never be a person's default leash choice, let alone one to try to use to teach good leash manners. Corrections are virtually impossible, often resulting in encouraging misbehavior instead of preventing or alleviating it. The point of a leash correction is to redirect unwanted behavior. The best redirection in my experience is turning away from whatever stimulus is causing misbehavior. If a dog is moving toward something of interest and pulls a leash taught, it's easy to real them in with a standard six foot leash. With a retractable leash, however, there is much more distance in the leash itself and the internal mechanisms do not have an automatic rewind. As the length of the leash is thin in comparison to a standard leash, it is harder to get a firm grip on the material. If one tries to use the retractable nature of the lead to reel the dog in, it isn't difficult for the dog to instead gain more distance from its handler. I have seen this occur on multiple occasions. There are reasons why trainers do not use retractable leashes during sessions.
Every dog I have ever seen walking on a retractable leash has been very badly behaved. Not only is there the reactive Doberman, but there are also two highly aggressive Yorkshire terriers owned by another neighbor. Those two are far worse, most likely because whenever another dog is near their owner will pick them up. I saw one of them turn from a reasonable little dog to just as awful as her housemate, snarling and nearly biting her owner trying to get to my dog.
They'll Probably Make Other People Hate YouFrom experience, I immediately become wary of two kinds of behavior in another person and their pet when I'm walking my dog. The first is a taught leash with a dog pulling forcefully against its collar or harness. The second is the use of a retractable leash. (Of course there are always off-lead dogs, but as I'm in a city I don't expect to see them.)
|Seeing this coming at me on a walk is my worst nightmare|
As retractable leashes encourage unrestricted movement, making it nearly equivalent to a dog running free. It is more likely for a dog to use that sense of freedom to charge at a strange dog. Since this is indeed aggressive behavior, there is a good chance that this will lead to a confrontation. Another concern is what the leash will do if and when it pulls taught. As I said, they are prone to breakage and most dogs on this sort of leash are usually poorly behaved.
Most Importantly: They're Very Dangerous for Everyone InvolvedThere is a good reason why they come with warnings. The thin material of the retractable leash can cause severe injuries if it becomes wrapped around any body part and then pulled taught. These vary from burns and cuts to complete amputations, particularly of fingers. The leach can also be a tripping hazard, especially the thinner lines which may be difficult to see if the handler and dog are a significant distance apart.
A dog running at full steam on a retractable leash poses huge dangers to potentially everyone nearby. The sudden jerk when the dog reaches the end of the leash can cause serious injuries to the neck. Not only that, but an owner can be pulled off of their feet and dragged. The leash handle is also very easy to let go of due to its bulkier build. Then, the dog is running free. The sound of the handle hitting the ground can be quite frightening, but even worse is being "chased" by the handle after trying to run away. The dog can easily dart out into traffic or be exposed to other dangers, such as other dogs. Depending on the temperament of the dog, it can also expose a danger to other dogs or people.
All in all, unless you have a very (and I mean amazing bombproof very) well behaved dog, just stick to a standard leash. They're cheaper and safer and make it easier for everyone in your community to live without the need confrontation.
Images are from Flickr.com and are under Creative Commons licenses: 1, 2.