Why I hate Frontier Airlines
This is my story. YMMV.
Frontier is always shouting at the top of their lungs about how good their frequent flier program is. Only 15k miles and you get a free flight! If we required truth in advertising, they'd be forced to say "Only 15k miles and you earn a right to a flight that you might get to use if you book at least 5 months in advance and don't mind flying at the most inconvenient hours!"
Or, like I heard this morning: "You can fly from Denver to Vegas, but you'd have to be routed through Memphis. Oh, and you can't come home until Wednesday."