正 stacks a foot 止 beneath a line marking the destination: walking straight toward the target, no swerving. Straightness became correctness — the moral geometry Chinese loves.
正 is rightness in every register: 正在 (right now, in the middle of — 我正在学习, I'm studying right now), 真正 (genuine), 正常 (normal). Chinese tally counts use 正 — its five strokes make it the native tally-mark: shopkeepers count 正正正 where the West scratches four bars and a slash. Confucian texts demand 正名 (rectifying names) and a 正 posture for a 正 heart — geometry as ethics, five strokes at a time.
A foot 止 walking dead-straight at the line 一 — CORRECT.
Chinese tallies in 正: each completed character = 5. Count a restaurant's queue slips and you'll see columns of 正正正.