The standard verbiage typically for gas engines is X,XXX miles or once a year which ever comes first. Some other vehicles are 5,000 miles (some 7,500 miles) or once a year which ever comes first. Those with oil change indicators usually say change oil when the indicator tells you to or one year which ever comes first.
Personally in my small block Chevy 350 engine I use 5W30 Mobil I and change once a year or 12,000 which ever comes first and for me I hit the 1 year limit first most the time. If I lived in a dusty area of the country I would change every 3,000-5,000 miles and not use Mobil I.
Len & Joanne
The Green TARDIS