The movement is the engine of the watch. Its type determines the energy source, accuracy, service frequency and, in part, the experience of wearing it.
The quartz movement
A piezoelectric oscillator — a quartz crystal crossed by an electric current — vibrates at 32,768 Hz. A divider circuit counts these vibrations and triggers the hands at regular intervals.
Accuracy. Around ± 15 seconds per month for a standard quartz. Thermally compensated movements reach a few seconds per year.
Maintenance. It comes down to a battery replacement every two to five years. No mechanical service required.
Use. A quartz watch does not need to be worn or wound. It restarts without adjustment after a battery change. It is the most reliable solution for watches worn occasionally.
The manual mechanical movement
The mainspring is wound by hand via the crown, daily or every two to three days depending on the power reserve. No oscillating weight, thinner case, direct transmission from gesture to mechanism.
Accuracy. ± 2 to 6 seconds per day for an uncertified calibre. COSC-certified calibres reach ± 4 seconds per day on average.
Maintenance. A service every five to eight years depending on the manufacturer, covering ultrasonic cleaning, lubricant replacement and tolerance checks.
Use. Daily winding is a ritual for some, a constraint for others. It sustains a direct relationship with the object.
The automatic movement
The rotor — a half-disc articulated on the movement — converts wrist movement into mainspring winding. A watch worn regularly does not stop.
Accuracy. Identical to manual winding for the same base calibre.
Maintenance. Same service frequency as a manual.
Use. A watch kept wound by wearing is the solution that balances convenience and mechanical interest. Left aside for a few days, it stops — a watch winder can take over.
What does not change
Whatever the movement type, water resistance, shock resistance and material quality depend on the care given to the case, not the calibre. A precision quartz in a poorly assembled case keeps worse time in practice than a well-serviced automatic in a solid watch.