+1 to @oldtimer_11
Nothing magic about 1 year, but it is an easy thing to remember.
Your post states "avoid changing ....oil"
The best and cheapest thing you can do for your car is change the oil. You have a car worth $15K, replacement around $20 to $25k. $50 bucks for an oil change is a cheap way to keep the engine in good shape, not something to be avoided.
By products of combustion include water vapor. Unless the engine and oil get good and hot, the water vapor hangs around,mixes with all the un-burned junk and doing all manner of harm to the engine. Not a major hit each time, but little whacks each short run. These build up over time and wear away at the internals of the engine.