Tesla Motors (NASDAQ:TSLA) has guided for about a 50% boost in vehicle deliveries this year. For investors unfamiliar with Tesla's story, this number could sound a bit too optimistic. But as Fool contributor Daniel Sparks explains in the video below, not only is a 50% boost a conservative estimate, it's also the wrong area for Tesla investors to focus on. What will make or break Tesla is the company's long-term road map to ramp up supply.

Demand isn't a problem for Tesla. Not only does the company sell every vehicle it makes, but it hasn't spent any money on advertising. And, going forward, Tesla has no plans to initiate any paid advertising. Understanding this context is crucial for investors interested in the electric-car maker.

With more than enough demand amid Tesla's global rollout, investors should shift their focus from this year's delivery figures to Tesla's long-term plan to boost supply, Daniel says. Supply, he explains, is the ultimate story for Tesla investors to watch.

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