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If you come prepared for a situation; most instances the object you brought will not be necessary. Much like bringing an umbrella because of rain in the forecast, but since you have the umbrella, it isn't raining, or won't rain at all.
Ron: Of course it isn't raining the day I bring my umbrella with me.

Mike: Umbrella rule dude, it'll never rain whenever you come prepared.
by baked_12 April 05, 2011
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