Full ownership
For most consumers, the opportunity to purchase a car outright simply does not exist. Outright means that the vehicle is paid in full and the ownership has been transferred to you. With many cars priced in the hundreds of thousands, most buyers just don't have that kind of capital lying around.
Related: How to get the best deal when buying a car with cash
If you do happen to find yourself in the position to purchase a car outright then that is the best situation. The old saying is that a paid-up car is the best car. Anything that you don't owe money on becomes an investment.
Score!
The other side of the coin is opting for putting down a hefty deposit and paying off the vehicle to buffer your credit score. Having no credit score is just about as bad as having a bad one. If you have other means of maintaining your credit score and can afford to buy cash then this is naturally the best option.