How is this different from just having a budget?

Detailed Explanation

A budget sets the allocation; the pause enforces it at the moment of decision. Most budgets do not fail on arithmetic. They fail in the seconds between wanting something and buying it, which is a behavioural gap that no spreadsheet closes on its own. So they are complements: the budget is the plan you check against, and the pause is the habit that makes you check. Neither is much use without the other.