The mundane enemies
People imagine watches are endangered by catastrophe — the drop, the dive, the collision. In practice the things that actually degrade a watch in daily life are quiet and ordinary: the magnetic field of a laptop speaker, the cumulative shocks of an active wrist, a temperature swing, a missed crown. A mechanical watch is more robust than its reputation in some ways and more vulnerable in others, and knowing which is which lets you wear it freely without either anxiety or carelessness.
Magnetism: the invisible disruptor
The most common cause of a watch suddenly running fast — sometimes minutes a day — is magnetization. A mechanical watch keeps time by a hairspring whose coils must breathe freely; if the spring becomes magnetized, its coils cling together, the effective length shortens, and the watch races. The culprits are everywhere in modern life: laptop and phone speakers, tablet covers and bags with magnetic closures, induction cooktops, headphones, and the magnetic clasps on some accessories. A watch laid next to any of these regularly can pick up a field.
The good news is that magnetization is harmless and completely reversible. A watchmaker can demagnetize a movement in seconds with a simple tool, and inexpensive demagnetizers exist for home use. If your watch abruptly starts gaining time, suspect magnetism before anything else — it is the first thing a watchmaker checks. Watches with anti-magnetic protection (a soft-iron inner cage, or a silicon hairspring immune to magnetism) resist the problem; if you work around strong fields, they are worth seeking out.
Suspended near a cheap compass, a magnetized watch will visibly deflect the needle as you bring the case close and rotate it. It is a crude but genuine test, and it confirms in seconds whether the cause of fast running is magnetism — fixable for free — rather than something requiring service.
Shock: what a movement can and cannot take
Modern movements include shock protection — a sprung mounting (Incabloc and similar systems) that lets the delicate balance pivots move under impact instead of snapping. This makes watches far tougher than their fragile-looking interiors suggest; ordinary knocks, sport, and an active life are generally fine. What shock protection does not fully cover is the sharp, concentrated impact — a watch dropped onto a hard floor, or a direct blow against a doorframe — which can still shear a pivot, displace the hairspring, or crack a jewel. The practical guidance: wear the watch normally, but be aware that the balance and the hands are the vulnerable parts, and a hard direct hit, especially to the crown, can do real internal damage even when nothing looks wrong from outside.
Heat, water, and the crown
Three more habits matter. Heat stresses gaskets and thins oils; keep watches out of saunas, hot tubs, and direct prolonged sun (a watch left on a hot dashboard is being cooked). Water belongs only to watches rated and recently tested for it, and never with the crown unseated. And the crown is the single most important habit: on screw-down crowns, the discipline of always threading it back down is what stands between the movement and disaster, because every other seal is irrelevant if the crown is open. Most water damage is not a failure of the watch; it is a forgotten crown.
Resting and storing
When not worn, a watch wants little: somewhere dry, stable in temperature, and away from magnets. A simple watch box or drawer is fine; a safe adds security. Store watches wound down or let them stop — a resting movement is in its most benign state. Avoid leaving a watch crown-down on a hard surface where the stem takes the weight, and keep leather straps out of damp, which rots them. None of this requires special equipment. The whole of everyday care reduces to a short list: keep it off magnets, off heat, away from hard direct blows, and never let the crown sit open near water.
A watch does not need to be coddled, but it does need to be understood. The real hazards are the dull ones — the speaker that magnetizes it, the doorframe that shocks it, the shower that floods a forgotten crown — and all of them are avoidable with habits that cost nothing. Protect against the mundane enemies and a mechanical watch will absorb an ordinary life without complaint, which is, after all, what it was built to do.