Tesla Inc. shares slid 7% Tuesday to bring their two-day loss to more than 9%, as analysts weighed in on lower-than-expected second-quarter deliveries and questioned whether the achievement of a key production goal is sustainable.

Adding to the downdraft was a Business Insider report that said internal documents showed Tesla Chief Executive Elon Musk ordered his employees to stop putting nearly finished Model 3s through a critical safety test before leaving the factory floor. A Tesla spokesperson told the website that every car goes through “rigorous quality checks.”

The electric car maker reported on Monday that it delivered 40,740 vehicles in the second quarter, “another significant miss vs. consensus of 48,874 and JPM’s 56,600 (Tesla deliveries also fell short in 1Q18, 4Q17, and 3Q17 — ever since the Model 3 entered production),” JP Morgan analyst Ryan Brinkman wrote in a note.

Brinkman said the company’s success in finally meeting its goal of producing 5,000 of its Model 3 mass-market sedans a week, was likely aided by the past practice of unsustainable “burst production,” where it pulls out all the stops to meet a goal that cannot initially be repeated.

In-transit vehicles are not being counted as sales for the period, suggesting less fixed overhead absorption, he said, which could mean higher costs given the way that Tesla TSLA, +1.95% met the goal. The company built a production line in a tent beside its main factory, a construction that is expected to be temporary.

JP Morgan lowered its revenue and earnings forecasts after the report and said it’s sticking with its underperform rating on the stock, the equivalent of sell.

Bernstein analyst Toni Sacconaghi was also downbeat on the report, and said the key issue for the Model 3 is not production but profitability. Tesla said it still expects to be profitable and cash flow positive in the third and fourth quarters, but “we believe that even if Tesla does hit these targets, it will likely be due to one-time austerity (working capital, opex) and/or product mix (4WD and performance version) factors ... and will not resolve the fundamental controversy of long-term Model 3 profitability.”

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The analyst further questioned Tesla’s claim that production on the new line offers the same quality as the regular line: “ We question whether Tesla can really evaluate customer satisfaction yet, when 11,166 Model 3s (likely including a majority of those manufactured on GA4) still remain undelivered in transit,” said the note.

Sacconaghi further questioned whether the tent will be maintained indefinitely and whether the mostly manual work being performed on it can be automated and at what cost. If Tesla did not have room in its Fremont plan to build capacity for 5,000 cars a week, how will it manage 10,000?, the analyst asked.

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Still, the longtime bulls took a different tack, with at least two analysts reiterating ratings that were the equivalent of buy. Baird’s Ben Kallo described the deliveries report as a “solid release,” which he predicted would lead to sustained stock strength, once the dust settles.

“We think Tesla has a differentiated ability to attract new capital, particularly as the company builds out its business,” said Kallo. “We continue to believe Tesla has access to capital markets, particularly as the company achieves production milestones and continues to build out its business.”

Instinet analysts led by Romit Shah said the company met an important milestone, “that we believe reestablishes some credibility and positions the company for profitability in the second half of the year.

“That said, we continue to expect TSLA shares to be volatile near term; we see current weakness as an opportunity to further accumulate shares,” Shah wrote in a note.