In mechanical watchmaking, friction is the primary enemy of energy efficiency. In the traditional Swiss lever escapement, approximately two-thirds of the energy accumulated by the mainspring is dissipated as heat and wear before reaching the balance wheel: a figure I have always found striking, and one that explains why the industry has never stopped seeking alternatives.
Solutions fall into two major families. The first addresses materials: synthetic rubies in bearings have reduced sliding friction since the nineteenth century, but contemporary solutions push further. Silicon — used by Patek Philippe, Rolex and others for escape wheel pivots and wheels — is lighter than metals, does not corrode, requires no lubrication, and does not react to magnetic fields. IWC added a diamond coating to silicon components through its Diamond Shell technology; Ulysse Nardin does the same with the DIAMonSIL process. The second family addresses escapement geometry: the detent escapement provides direct impulse without sliding friction, but it does not self-start and cannot withstand daily shocks. George Daniels spent decades reconciling the properties of Breguet's natural escapement with practical use, reducing friction nearly to zero while maintaining self-starting capability. Omega's Co-Axial escapement, later acquired and industrialized, reduces sliding friction by partially replacing it with rolling friction. Grand Seiko's Dual Impulse Escapement transfers energy both directly and through the fork, spreading the load and lowering overall friction.
Then there are hybrid solutions. Breguet experimented with magnetic pivots that center the balance staff with opposing fields, virtually eliminating physical contact in end bearings and allowing oscillations at 10 Hz with reduced consumption. Zirconia ball bearings — seen in the Kudoke 5 — require no additional lubrication. Girard-Perregaux's Gyrotron system replaces ball bearings with rubies on fixed supports.
Even seemingly peripheral components affect friction: a longer, thinner mainspring accumulates energy over more turns, lowering tension per turn; a dual-hairspring like that in H. Moser & Cie's HMC 805 improves isochronism by limiting friction variations during oscillation. The friction-fit bezel is instead a case where friction is intentionally used as a locking mechanism, accepting its limitation: it can rotate accidentally.
From the bench I see the practical consequence of all this: movements that manage friction better maintain regulation longer between service intervals and better withstand temperature and positional variations. Chronometer certification is difficult precisely because every degree of friction translates into frequency drift.