Tesla took a huge risk by taking a completely new technology (battery-powered cars) and applying it in a completely new and untested way (performance car). They went into it knowing that they'd be taking a loss for the medium term.
If Tesla are already at taking only a $4k loss / 10% loss, they're doing extremely well:
- The "Supercharger" units that are being aggressively installed across many countries will be accounted for within this unit cost... It won't be long until they reach diminshing returns on their deployment, and the impact of this will tail off.
- They added a number of new product lines, all sinking huge money into R&D. They're close to establishing a range of products so the impact of this will tail off shortly.
Musk could easily choose to add $4k to the sale cost of each cars with minimal impact and result in a 0-dollar P/L, but increasing production count ensures far better long-term return by economies of scale improvements, as well as learning opportunities when scaling aggressively.