They also originate in a totally different way, from follicles inside the skin in a manner akin to hair. Clearly, the information required to code for the construction of a feather is of a substantially different order from that required for a scale. For scales to have evolved into feathers means that a significant amount of genetic information had to arise in the bird's DNA which was not present in that of its alleged reptile ancestor. As usual, natural selection would not favor the hypothetical intermediate forms. Many evolutionists claim that dinosaurs developed feathers for insulation and later evolved and refiner them for flight purposes.
Anther problem is that selection for heat insulation is quite different from selection for flight.
On birds that have lost the ability to fly, the feathers have also lost much of their structure and become hair-like. On flightless birds, mutations degenerating the aerodynamic feather structure would not be as much a handicap as they would be on a flying bird. Therefore, natural selection would not eliminate them, and might even select for such degeneration. As usual, loss of flight and feather structure are losses of information , so are irrelevant to evolution, which requires an increase of information. And hairy feathers are adequate.