And always carry a rabbit's foot. Just as well-thought out decisions are useful, random decisions can be even better. Why pick the movie you wanted to see when chances are it is awful. People make fun of blondes and their sometimes witless decisions. Because they have not the slightest remorse after making a decision.
Many people make a decision, only to regret it.
Thus, if you use your money to enjoy a milk shake, you cannot then allow yourself to feel bad because you will not be able to read the magazine. Decisions are supposed to make us happy. Thus, regretting a decision is contrary to happiness. Never look back. And you can always steal the magazine from a neighbor.