Traps that are used by beginning trappers will catch just as much as the professionals once they learn how to use them. After the beginning trapper learns how to properly use baits, lure and make each set a good one, he becomes a good trapper. When he learns the habits of the animal he pursues and the type of sets to take each animal he will graduate into the ranks of a professional trapper. This of course takes time and a lot of years trapping. As you can see, trapping is something you have to learn by actual experience. It cannot be learned by reading books only.
This is merely a guide to help you get started. Don't be discouraged if you do not catch a lot of fur at first. Keep notes of the types of sets, baits and lures being used. You will not become a successful trapper if you are not observant.
Join your state's trapping organization and go to the club's meeting. You will meet a lot of trappers who will answer your questions. Demo's of different sets are explained in detail. Practice what you learn and you will be successful.