For smooth running, a CV joint uses a special lubricant that is packed in and then sealed by plastic or rubber boot secured with a pair of clamps. As long as that boot is undamaged, the CV joint should last a long time without maintenance.
It is more likely that your car will rust through before the CV joint goes. However, a damaged or cracked protective boot opens up a whole world of pain as lubricant spills out and water infiltrates the joint.