Where the shape comes from
An old person with long unbound hair, bent over a stick: the top strokes are the hair and the stooping back, and the 匕 at the foot is the staff taking the weight. Age meant standing, so 老 became a mark of respect — 老师, 老板 — and a marker of long acquaintance, 老朋友. Reduced to 耂 it caps 考 and 者.