If you take a character and you call him a frog, or like Rowlf, our dog, call him a dog, you immediately give the audience a handle.
Actually the copies of characters is something I don't particularly like to talk about in articles but just for your information, most characters there's only one.
If you're doing a large, complicated character with radio controls, it might take a number of people several months to make it and if you're talking about a quick little hand puppet, it could be made in 2 days, so there's enormous range there, and no real easy generalities.