Due to the fact that Leatherworking is a Primary Trade Profession in World of Warcraft, you must be 100 % sure when making a selection of this profession that it is an occupation that you want to practice and learn the most. As a Primary Trade Profession, this is just because Leatherworking counts toward your restriction of Two Primary professions in the game.
Another most important thing for all players to keep in their mind is that if you decide to choose Leatherworking as your Primary Trade Profession in the World of Warcraft, it is deemed necessary to have the skinning skill as your second Primary Profession to be supplementary to this profession because skinning and Leatherworking always go along very well exactly like Alchemy and Herbalism or Jewel crafting and mining.
Of course, you also can unlearn a profession whenever you want to at any time but that also means if you ever want to learn it again, then you will have to restart completely from the beginning because all the skill points that you received while utilizing that profession will be lost. Hunters and Shamans are the character classes in the World of Warcraft who likely get the most benefits from this Leatherworking profession. However, it also partly benefits Druids and Rogues during their early levels as they are not able to use the mail Armors that are created at the higher Leatherworking skill levels.