Braces and other supportive devices are great to use when recovering from an injury and to prevent re-injuring a joint that is still unstable from a previous injury.
Braces can give the joint the support it is lacking because of poor ligament stability or weakness of the muscles surrounding the joint. However, your ultimate goal should be to restore your joint's strength and stability so that it can support itself without a brace.
Therefore, I do not recommend using braces or wraps if there is no medical need for them. This doesn't mean that if you were to fall or get hit that a brace may not help prevent an injury, but there are many cases in which injury can occur even with a brace.
The bottom line is, use it if it helps to provide support that your joint lacks due to injury, but do not use it if no injury is present. You want to train your muscles and joints to support themselves without an assistive device. You can do this by stretching and strengthening the joint and its surrounding muscles, which also helps you recover and prevent further injury.