RE: [Demo notebook] Reference notebook: corrections and recurring beginner questions · RWI-02416

Case 38 — Maintenance question: how do I tell if an automatic actually needs service? · source wording exercise

Common advice says service every five years, but service is expensive and some people run watches much longer. What observable signs actually indicate a mechanical watch needs attention, as opposed to just being due on a calendar?

Review focus: source wording. Retain the source wording beside any paraphrase. Use the original answer fragment “Useful signs, in rough order of seriousness: power reserve noticeably shorter…” as the discussion anchor; no new event or result is supplied.

Exercise RWI-02416/38: address this question within its stated limits.