A 22-year-old woman presents with sudden-onset patchy hair loss on the scalp first noticed 5 weeks ago. On dermoscopy at the periphery of the affected patches, short hairs are identified that taper proximally toward the scalp and are broader distally with a broken frayed distal end. The structure marked **B** in the diagram represents these pathognomonic findings. Which of the following best describes the clinical significance of the structure marked **B** in alopecia areata?