Before quartz (and cell phones) how did people ensure the time on their watch was accurate?

Basically as the title says. Anyone have anecdotes from this era?

Today’s top automatics lose a few seconds a day, which is great and all, but accuracy is essentially irrelevant since we don’t really use watches to tell time (some mission-based and medical uses will be an exception to this). Notifications from phones, smartwatches, computers and admins keep us running on time for important things. Watches are jewelry - and there’s nothing wrong with that.

But in the past, mechanical watches were the main way to tell time accurately. However a truly accurate wristwatch for the general public (i.e., quartz) wasn’t invented until the 1960s. That meant there were ~80 years of people trying to catch planes, trains and automobiles using a device that may have lost/gained quarter-minutes or more each day. Over the course of a month or two that could lead to a watch being off by multiple minutes. This would be a nuisance for things like business meetings and medical appointments, keeping people waiting, but could be a deal breaker for transit.

So how did people keep their watches accurate? Was there a number that people called regularly? A master timekeeper in town that people visited after Sunday mass? Did corporations offer time-setting and watch calibration as an employee benefit? Or did people simply operate in a world where being “on time” meant the possibility of waiting for a few minutes for the counterparty?