GoKawiilApple Watches rarely need manual restarts, testing shows
A review of Apple Watch usage explains that watchOS manages background processes and system caches largely on its own, unlike the periodic reboots recommended for other devices. Apple recommends a restart mainly when storage is too full for a software update, and users can manually clear cached web data through Settings. Hands-on testing found some Apple Watches ran for years without a manual restart and showed no notable performance decline, since watchOS reboots already occur with each software update.