It's ok for NA cars but not for turbo-charged cars... because of extra heat due to forced-induction and bad driving habits, the oil tends to disintegrate even before the 5000km or 10000km service intervals.

I service my car every 5000km but sometimes lower say 3500km or 4500km depending on driving style. If always cruise with minimal boost, service every 4500km. If not, 3500km and by then, the oil is usually thick and black.

A good oil and proper service intervals will ensure a problem-free engine for many years to come. Of course, proper driving style must be taken account of too.