Lubricants with an oil base are most commonly used for masturbation; many sex experts discourage oil-based lubes for penetrative sex, since they can leave a coating that increases the chances of infections. Oil cannot be absorbed by your body which can cause the lube to sit idle inside of you for extended periods of time, not necessarily a good thing. The main advantage of an oil-based lube is its staying power. These lubricants last for an exceptionally long time.