A good analogy is if you've ever tried to eat healthier and cut out most junk food from your diet. If you're anything like me, that is a LOT easier if you don't have a sleeve of oreos in the fridge and a quart of ice cream in the freezer, at least at first. Maybe after months and months of dedicated dieting, you can allow yourself to indulge in 1-2 cookies after dinner, but when you're first getting started, a cold turkey approach can be much easier, as you have to exercise a lot less willpower if the temptation isn't readily at hand.