It's highly likely that new players of the Magic: The Gathering trading card game, aren't really aware of how important it is to protect their deck. Seasoned players are more aware of this aspect.
Cards can easily get damaged during play through shuffling, from the oils on the skin, and even when they're not used if they're not properly stored. You'll want your cards well preserved because some of them have a pretty high value if you'll ever consider selling them by piece.
Owning a deck box designed by the same team that designed the cards, sounds like the most natural choice. The box you can see here is specially made by the MTG team and can hold only one deck of cards.