At a basic level, owners want dogs with which they can pleasantly share a house, a car, or a walk in the park. Some dogs need only a minimum amount of training to learn to eliminate outside (be housebroken), to sit, to lie down, or to come on command (obey a recall). Many other dogs prove more challenging. New dog owners might find training difficult and fail to make progress, because they expect dogs to think and act like humans, and are surprised and baffled when the dogs don't.
Before enrolling with a particular club contact them and ask if you can go to watch a class without your dog. This will help you decide if this is the right environment for you and your dog. Some clubs have waiting lists and you will need to book ahead, some accept people on a roll on roll off basis. Prices will vary from a joining fee and then weekly payments to a one off fee for a certain length of training.