In the descriptive sense, people speak of luck after events that they find to be fortunate or unfortunate, and maybe improbable. Therefore, cultural views of luck vary from perceiving luck as a matter of random chance to attributing to such explanations of faith or superstition.
Chirping can be due to misalignment of the drive belt, but could also be due to pulley misalignment, worn pulley bearings, worn belt ribs, contamination from oil, coolant, power steering fluid, brake cleaner, belt dressing, or other substances. Squealing is usually caused by slipping between the belt and the pulleys.
If brakes on a vehicle make any type of noise under driving and braking conditions, it is the sign of a malfunction. Noises may be a variety of brake and brake mounting systems failures, or they may be other problems that occur when the motion of braking creates movement in another part.