The main argument for buying is "equity"—eventually, you own the car. The argument for leasing is "lower payments." However, cars are depreciating assets. "Owning" a 10-year-old car isn't like owning a home; it's often a liability requiring expensive repairs. Leasing ensures you are always driving a car under warranty.
Leasing is only cheaper if you drive less than 10,000–12,000 miles per year. If you have a long commute, the "excess mileage fees" at the end of a lease (often $0.25 per mile) can cost you thousands, making buying the far better option.