It’s been two years since Elon Musk changed the name of his company. Like Apple Inc.’s decision a decade ago to hit delete on “Computer” (nodding to its focus on mobile devices), he dumped the “Motors” from Tesla Inc. to send the message that his was more than just a car company.

The move has flopped. Yes, Tesla now offers batteries and solar panels for homes, but all investors care about are its sleek electric cars.

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