This suggests that a reaction from consumers who dislike Mr Musk’s antics are only one reason for falling sales. An updated Model Y, Tesla’s best-selling vehicle, has just gone on sale. In preparation Tesla ran down inventory of the old model, crimping supply. Customers doubtless held off purchases until the new car was available.

Elon Musk made good on his promise to appeal a controversial decision by a Delaware judge who wiped out his $56 billion performance-based compensation plan as the Tesla CEO leads a revolt that is roiling that state’s politics.