Wasn't it in multiple letters to shareholders? It is literally an update to debtors on the company's position, far from arbitrary.
Were Tesla required to give an estimate? Nope. But doing so may be used to attract further investment into the company, so it is far from innocent.
There are two things you could disagree with but you don't specify which. You can disagree that Tesla set this goal for itself, or you can disagree that the number 5000 is arbitrary.
To disagree with the first part, you'd need to show that the 5000 figure came from an external party, do you have such a source for this?
To disagree with the second part, you'd need to show that there is something significant about the number 5000. Is your claim that there is some significance to the number 5000?
If you can't substantiate the claim that some external party gave Tesla the goal to make 5000 vehicles per week, and you can't substantiate the claim that the number 5000 has some fundamental significance when it comes to car manufacturing, then you have no grounds to refute the statement that Tesla set this arbitrary goal of 5000 for itself.
Debtors are people who owe you money. The word you are probably looking for is “creditors”, who are people you owe money (e.g., corporate bondholders.)
But, while it's closer, stockholders aren't those, either.
Unthinkable? Their Q4-16 Shareholder letter [1] (Feb 22nd, 2017) stated: "Our Model 3 program is on track to start limited vehicle production in July and to steadily ramp production to exceed 5,000 vehicles per week at some point in the fourth quarter and 10,000 vehicles per week at some point in 2018."
On July 2nd, 2017 Musk forecasted [2] 20,000 per month by December '17.
[1] http://ir.tesla.com/static-files/1ff901ba-bb25-4264-9153-7aa...
Giving this the new estimate is placed to summer 2018.
When that was missed, it was pushed back again to Q2-18. It looks like those shifting goalposts have finally been met but for the above poster to call it "unthinkable" is absurd. It's the exact messaging we've been hearing for at least a year and a half.
[1] http://ir.tesla.com/static-files/d68bddfe-6f2b-4f8f-bed0-94d...
That's the important thing. A lot of people are concerned about Tesla's ability to raise money and stay solvent. Tesla will not be profitable, or even cash-flow positive, until enough Model 3 cars are made.
Every month Tesla fails to reach a high-degree of production, Telsa loses another $75 million.
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The worst part about this rampup effort is how bursty and unreliable it is. Its going to be a one-week hit of 5000. Next week, or even next month, Tesla's sustainted output will be well below 5000, and therefore Tesla will remain unprofitable for another few months at minimum.
That's not even factoring in all the costs Musk threw down for these tents (Obviously a temporary arrangement, as a single storm will put those tents out of commission).
But the thing is, they did triple their q1 production, going from 9.7 to 28.5k so they almost trippled, or went from an avg of 9/12 weeks to 28/12 weeks, a clear increase. The newly announced goal is 6k by the end of August. It doesn't matter if through super-human work they get one week that is good, we can just measure their performance by total production, so I'd guess at least 50k would be another significant increase. It won't be 6k*12 weeks in q3.
Lost in this is the significant additional revenue they get. They aren't making their cheapest cars yet, so at 50k each, that last week alone was 250 million additional revenue. That 28.5 cars is about 1 billion more in revenue than q1. If they double that again, you are talking real money :-)