If you never plug it in, you still have a fully-functional vehicle.

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And he was never told to plug the car in overnight in cold weather, despite repeated contact with Tesla.

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If that disappears and there is a competitor to defect to, then the result could be a leak of users you will never be able to plug.

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But the temptation to plug in and never log back out again is strong.

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The document also gives you an option to say whether you want doctors to be "positively certain, " "certain to a high degree" or "reasonably certain" that you will never recover before pulling the plug.

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In fact, most folks never lift a finger to calibrate their displays, plug better speakers in, or place those speakers in actually advantageous spots.

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The company offered it free of charge to owners of WinMo 6 and 6.1 devices earlier this year -- but Microsoft taketh away just as quickly as it giveth, apparently, because it's already pulling the plug on the tool at the end of December, which never actually made it out of "Technology Preview" status.

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