Cramer never hesitates to admit when he made a mistake. His mea culpas are a regular occurrence on Mad Money. But that’s because you become a better investor when you honestly review what went wrong. Do that, and history is less likely to repeat itself.

So on Friday Cramer returned to two stocks – L-1 Identity Solution and Tessera Technologies – that didn’t perform as expected. Watch the video to see what went wrong in these names and the lessons learned as a result. The Mad Money host even created a new investing rule based on what he found.

Call Cramer: 1-800-743-CNBC

Questions for Cramer?

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