One reason why most people find it hard to save money is because the moment they see something they like or when they think they've stumbled into a great deal, they want to buy the item immediately. To avoid wasting your money thusly the wiser option would be to wait 30 days before making the purchase. It will give you time to find out whether you can do without what you intended to buy or not. If you realize that you actually don't need the things you wanted to buy, you'd have saved the money
I don't think that 3-day rule is applicable to me because I am not really an impulsive buyer. Shopping is enjoyable when it is planned because I don't have to worry about payments - planned purchases have a budget, of course. However, when we buy expensive items like appliances, it takes us months to decide after surveying the stores. When we planned to buy a new car, it took us more than 1 year to decide.
I do this for bigger purchases like electronic devices because I like to make those purchases with as little amount of impulse as possible so I know my decisions are as clear as they can be. However, sometimes it is unavoidable as there are certain promos I don't want to miss out on and unless I know the item will still be there in the future and another promo period will come up with the same amount of discounts then I probably will just take a leap and buy it then and there.
Fortunately I'm not an impulse buyer - as waiting 30 days before deciding to buy something wouldn't work too well for me - in fact as I've always believed that the best way of avoiding unnecessary purchases - is to only buy something if its actually needed - as well as only replace items when its absolutely necessary and then always look for the most cost effective option - it would more likely be a major inconvenience. However, that said - as the 30 day rule is a very valuable tip - that has proved to be very successful in helping many people adopt new habits or break old ones - I can definitely see how applying it to purchases - would be very worthwhile for impulse buyers - especially as the end result would be savings rather than debt.
This is a useful tip but I exercise a different version of this whenever I'm feeling like I want to buy something that I don't need. In my case, whenever I feel the urge to buy something that's way out of my budget, I try to go home and immediately think about the decision that I'm going to make. I try to list the pros and cons if I were to spend the money on something that would not help my business or investments. Since I care about my business life more than anything else in the world, it's usually enough to hold myself from buying that extra electronic gadget, or new shirt, for the sake of my investments.
If the item is quite cheap and affordable then I don't think I would want to wait another 30 days to buy it, I would be buying it asap. However, if the item is expensive then I certainly will take time in waiting before buying it to see if my interest in buying it will pass or not. If I still wanted the item after quite a while then I will still buy it.
I don't think that I would ever wait for 30 days to buy something, but I don't think there's anything wrong with waiting for one or two days just to see if the item is still something that you might want to buy. I impulse buy things sometimes and I know for a fact that if I had waited a few days, I would never have bought the item in question. So I try to walk away from things most of the time, and will go back the day after if I still want the item. More often than not, I will have already changed my mind.
I'm a self confessed impulse buyer, so I really do try to curb it to save money. I already do this, but don't wait 30 days LOL If I really like something, I'll take maybe a week (at most 2) to ensure that I really like it, that I actually need it and decide if I can really afford to buy it at that point in time.