Counter-intuitively this is especially true with international flights... The main stressor for a plane is not like a car, where it's miles driven/flown. Its in pressurization/depressurization. And so a plane doing domestic skips an hour or two away will wear out way faster than one doing transatlantic trips, and so you're more likely to see the shiny new plane on a short domestic trip than on a big international one.

Incidentally this also applies similarly to risk issues. The biggest risk in a flight is not in flying, but in takeoff/landing. This is why the commonly cited deaths/mile metric is not only misleading but completely disingenuous by the people/organizations that release it, knowing full well that the vast majority of people don't understand this. If some person replaced their car with a plane (and could somehow land/take off anywhere), their overall risk of death in transit would be significantly higher than if they were using e.g. a car. 'Air travel being safer than cars' relies on this misleading and meaningless death/miles statistic.