[MarkMc]

You are missing the psychological element. In general, people:

(a) Feel a strong obligation to be consistent with past behaviour - not just in placing the deposit, but then thinking and reading about the new car design and wanting a Tesla for months or years.

(b) Want to avoid admitting the 'mistake' of giving Tesla a free loan. Not just admitting the mistake to themselves, but also to all their friends they told about their deposit.

(c) Hate giving up something they 'own' - ie. their place in the queue

(d) Value something that's scarce more than something that's easily available

(e) Are more likely to want something that other people love and are queueing up to buy.

[MarkMc]

Thinking about this a bit more, Musk should run a split test: Half the people queued for a Model 3 are offered $100 to move to the back of the queue. People who decline such an offer will feel compelled to buy the car when it is released in order to be consistent with their previous actions. I'm confident this would boost sales, but the split test would tell us for sure.