I never learn my lesson. When we were in NYC last week I saw the greatest pair of shoes, but didn't try them on and didn't buy them. Then, I checked with the store here and they don't have them. It's a hard lesson to learn. The same thing happened when I was in London last year.
All the money books tell you not to buy something on instinct the first time you see it. But they don't know how to help you deal with the shoe letdown. And not even Bluefly can cheer me up.