When demand is unexpectedly high for a particular model, the capacity on the factory production line is pushed to its limit and delays begin to occur. A manufacturer is forced to cope with a backlog of orders which can push the delivery lead time back by a few weeks or even months.
These supply chain issues can often mean that vehicles in production are unable to be completed due to delayed parts, leading to further delays and changing delivery dates. In many cases, cars are taking more than six months to be delivered.