Tesla said it was unable to secure enough transportation at a reasonable cost.
To add to that, an unusual gap of more than 22,000 units between production and deliveries has spooked investors.
That's despite Chief Executive Elon Musk promising "steadier deliveries" in the current quarter.
Tesla, which sees a delivery spurt toward the end of each quarter, said more of its new vehicles were in transit by the end of the third quarter.
Musk has set a target to grow deliveries by 50% annually.
Which implies Tesla would have to deliver more than 450,000 vehicles in the fourth quarter to meet its goal.
Last week Reuters reported that the electric vehicle maker has set an ambitious target to produce almost half a million Model Y and Model 3 vehicles in the fourth quarter.
Those two models account for about 95% of its output.
STORY: Tesla shares dropped over 6% in early trading on Monday (October 3).
