That one question has saved me more money than any budgeting app. I've walked away from clothes, gadgets, and random "good deals" that I completely forgot about a few days later. But when the answer is still yes after I've had time to think, I buy it without guilt because I know it's something I'll actually use. Being frugal hasn't meant saying no to everything. It's meant getting better at telling the difference between what I want right now and what I'll still value later.