Mechanical, automatic, quartz: what actually powers your watch.
Every watch answers one engineering question: how do you release stored energy so evenly that it can count seconds? The three answers — mainspring and escapement, self-winding rotor, vibrating quartz crystal — define everything you will ever pay for.
The spring and the escapement
A mechanical watch stores energy in a coiled mainspring you wind by hand. The escapement — a tiny gate that opens and shuts several times a second — meters that energy out in equal portions, and a balance wheel swinging back and forth sets the rhythm. It is a machine from the 17th century, perfected, and it is the reason a $500 Hamilton feels alive in a way no phone does.
The rate of that swing is quoted as vph: vibrations per hour. 21,600vph is three swings a second; 28,800vph is four. A faster beat generally means a smoother-looking seconds hand and slightly better resistance to shocks disturbing the rate. A slower beat generally means a longer power reserve from the same spring, which is exactly the trade Tissot makes in the Powermatic 80 to reach 80 hours.
Automatic: the rotor’s trick
An automatic is the same machine wearing a flywheel: a weighted rotor spins with the movement of your wrist and winds the mainspring for you. Nothing about it is inherently more accurate — it is simply more convenient, and slightly thicker for the privilege.
The thing nobody tells beginners is that an automatic still has a finite reserve. Take it off on Friday night, and unless it banks 70 or 80 hours it will have stopped by Monday morning. That is why the reserve figure on a spec sheet is a usability number, not a bragging number.
Quartz: the honest overachiever
Quartz replaces the whole drama with a crystal vibrating 32,768 times a second and a battery. It is roughly ten times more accurate than any mechanical movement at a fraction of the price, and the watch world has never quite forgiven it for that.
Solar quartz, as in Casio’s Tough Solar, removes the last objection by charging the cell from ambient light — no battery changes, no service interval. Radio-synchronised versions go further and correct themselves nightly against a national time signal, which makes them the most accurate watches most people will ever own by a margin no mechanical movement can approach.
Which one should you want?
If you want the object to be interesting, buy mechanical, and buy the longest power reserve you can afford so it is still running when you come back to it. If you want the time to be right, buy quartz, and stop reading watch reviews. Most collections end up holding both, for exactly those two reasons.
One more term worth carrying forward: hacking means the seconds hand stops when you pull the crown out, so you can set the watch to the second. It is cheap to engineer and its absence on an otherwise good movement tells you where the maker chose to save money.