Thomas Edison tried two thousand different materials in search of a filament for the light bulb. When none worked satisfactorily, his assistant complained, “All our work is in vain. We have learned nothing."  Edison replied very confidently, "Oh, we have come a long way and we have learned a lot. We now know that there are two thousand elements which we cannot use to make a good light bulb." Learn From Mistakes learn from the mistakes of others 

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