If you need an oil change in your vehicle and you keep driving without changing the oil then eventually the engine will not be able to lubricate properly and then the engine will stop running eventually as the bearings seize up.
When your oil change light comes on or it's been longer than 3,000 to 5,000 miles since your last oil change then you should change the oil.
Failing to change the oil when needed can result in a damaged engine because your bearings wear out faster.
Spending the money to get your oil changed often enough will save you thousands in repair bills or needing to buy a new engine, new vehicle etc.
I change my engine oil myself and change the oil every 3,000 miles and the oil filter gets changed as well.
You should always change the oil filter along with the oil as the oil filter gets clogged and dirty as well.
Oil and oil filters cost around $25.00 to $35.00 or so depending on the brand of oil you buy and oil filter.
It takes me less than an hour to change my own oil.
However even paying a shop to change your oil is well worth it to save your engine from costly repairs or breakdowns.
The oil is the blood to your engine so makes sure to change it often to extend the life of your engine.
Also engine sludge builds up in your engine too when your oil is not changed often enough and that engine sludge then prevents the oil from flowing through your engine as it should so the engines moving parts do not get lubricated properly.