Buses are usually the cheaper inferior option. While bus service doesn't inherently suck, buses are usually chosen because of cost not because they want to run a good service. This results in cost cutting of every portion of a bus network until the experience suffers. Dedicated lanes are not provided so buses get stuck in traffic. Bus stops without rain shelters or even a bench (versus full stations). Operating budgets get cut and then the interval between buses goes to 30 min. Service after 10 p.m. gets cut. The bus networks that don't suck are usually called "shuttles" and are underwritten by tourism districts, airports, and theme park operators.