One reason I like the old 18 size- the crown is easy to grip with my arthritic fingers.
The better watches were machined to extremely fine tolerances, and ruby and sapphire jewels, harder than steel, bore the spindles to the little wheels that went round and round, guaranteeing a long life.
Not perfect, but well-made. Watchmakers of the time always had a supply of repair parts. Even small towns along RR lines had a good watchmaker, certified by the RR, who could put a sick watch back to top condition.

Watchmakers capable of doing repair to old watches today took up the parts left over after the manufacturers ceased operation.
Last week I received back a watch of a great grandads. It needed a new mainspring, and a roller jewel. The watchmaker had the "new" old stock mainspring on hand but it took a while to locate the proper roller jewel, also new old stock.