Time has physical properties that can be measured but differs from other Measurement in that neither physics or politics has had their last word on scale.
Models project back to an absolute origin of time allowing us to talk about the age of the universe. But models don't provide a useful origin for things as small as a lifetime.
Leap seconds are introduced into our scale for time by a political processes that cannot be forecast. As a consequence, in spite of the fabulous accuracy of atomic clocks, we can't schedule anything in the future with precision greater than that of our wobbling earth.
Both issues complicate software where precision quickly exceeds even the most precise measurement.