This is indicative of a car that has been driven very hard(with frequent severe applications of the Brakes and/or exposure to cold water/puddles during such severe usage). That it has reached this level of damage suggests that adequate maintenance HAS NOT been a priority on this vehicle, IMHO.
Those cracks are to the point that the rotors should be replaced, but having small heat cracks in the face of the rotors is not unusual if they're being used heavily, ie track work. Next time you're at a race track have a look at the front brake rotors on a few race cars and they'll all have hairline cracks in the face. As long as the cracks don't get too big, and most importantly don't extend to the edge of the rotor, they're still fine to use. Do you know what brand those rotors are?
