Why use plenty of water-based lubricant?

When people use condoms without any lubricant on the condom, it is more likely to slip, or tear, because of increased friction.

Anal sex without lubricant can not only be painful, it also greatly increases the risk of tears and cuts to the lining of the rectum as well as the risk of breakage of the condom.

During vaginal sex, a woman produces natural lubricating fluids, but these may not be enough for safer condom use. The amount of fluid a woman produces changes throughout the menstrual cycle, and is influenced by several factors. It is quite natural for some women to need additional lubrication for comfort as well as for safer sex.

Oil-based lubricants weaken condoms drastically and dangerously within minutes. Often an oil-covered condom will split during sex, and the user may not realise it is burst or torn until after the event. If someone is desperate to have sex, and only has oil-based lubricant to hand, then it still shouldn't be used. Spit is preferable to an oil-based lubricant, although it does dry out quickly.

Penetrative sex without lubrication leads to increased friction, which puts extra strain on the condom. Adequate lubrication can sometimes be ensured in vaginal sex by means of plenty of foreplay but this is not always effective. Spit or water are not very good lubricants.