Many mistakes with money result from a lack of self-control. We think we'll control ourselves, but, when faced with temptation, we can't. Studies like Nordgren et al., (2009) show people are woefully optimistic in predicting their self-control. So, don't put yourself in the situation of being tempted. This is why cutting up credit cards is often recommended. We're mostly weaker than we think, so we shouldn't give ourselves the opportunity.

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