LEASE - If you enjoy driving a new vehicle every two or three years, want lower monthly payments, like having a vehicle that has the latest safety features and is always under warranty, don't like trading and selling used vehicles, don't care about building ownership equity, have a stable predictable lifestyle, drive an average number of miles, properly maintain your vehicles, are willing to pay more over the long haul to get these benefits, and understand how leasing works, then you should LEASE.
BUY - If you don't mind higher monthly payments, prefer to build up some trade-in or resale value (equity), like the idea of having ownership of your vehicle, prefer paying off your loan and being payment-free for a while, don't mind the unexpected cost of repairs after warranty has expired, drive more than average miles, prefer to drive your vehicles for years to spread out the cost, like to customize your vehicles, expect lifestyle changes in the near future, and don't like the risk of possible lease-end charges, then you should BUY.