Household Deficit

... commit to putting aside every month. Now imagine you overspend for Christmas and end up with $2,000 in credit card debt. You'll plan to pay it down using the money in your monthly "gift" envelopes since, after all, you spent it on gifts. And now ...

http://www.slate.com/articles/double_x/doublex/2013/04/the_envelope_method_for_household_budgets_is_a_bad_idea.html