A well-run production line produces about the same number of units per week. Tesla's weekly numbers are all over the place. Their cost per unit has to be very high, because the cost of running the plant is roughly constant as the output varies.
Eventually Tesla ought to get their plant debugged, but if they're doing assembly in a tent, that's in the future.
They also seem to be having trouble at the battery plant in Nevada, which is strange. That's a relatively simple product, and it's one they've built before.