I think I could better help you if I knew what kind of car and brake system you have.
For drum brakes, the star wheel is supposed to compensate for shoe wear, and determine when the e-brake becomes effective. With the e-brake off, you want a tiny amount of brake drag. Star wheels aren't perfect, that is why they sometimes need adjustment.
Other cars have rear disc brakes with a tiny brake shoe inside. I have often seen the miniature brake shoes fall apart, especially after a recent brake repair. Such systems also have a star wheel adjuster to try to compensate for shoe wear.
Sometimes the problem is that the cable between the e-brake and rear brakes becomes stretched, or one side breaks, making the brake system half as effective as it should be. This problem is more common where there is road salt.