Owning the system clock: Good enough?

Across numerous industries, accurate timing is a common requirement. Applications will read the system clock and expect this to be the actual real-world time. But how accurate is it actually necessary? And is knowing the approximate time better than not having any idea what time it is?Looking at our PTP operator more specifically, its responsibilities are threefold: managing receiving and transmitting time, controlling the system clock, and keeping metrics and raising events based on the clocks....