5. Hardware vs. Software
They develop Tesla cars like smartphones or modern computers. That means they have the running gear or drive train that are hardware and control systems that are software. Of course, the software gets regular updates to improve the performance, power usage, and comfort of the passengers.
However, sometimes, the updates are too advanced for the drivetrain. So, to keep up with the new version, you need new hardware or a new drivetrain. And that is not only costly, but it also requires technical support from a Tesla dealer.