Some women can do lipstick – the ones you never see without their signature shade; morning, noon or night, it's still in place, no fading or feathering.
Gwen Stefani is a prime example. Sure, there's probably a make-up artist just out of shot on official occasions, but even papped on the beach, her pillar-box lippy is weirdly consistently perfect. Presumably these women have made some deal with the devil (although not a very clever one if all they asked for was perfect lipstick).
Meanwhile, the rest of us barely make it through the commute without finding our lipstick has dried out or disappeared patchily. This is where most give up and plump for gloss. But the problem with gloss is that it's either too nothing-y or full-on, high-shine porno.
Enter the lip pencil – halfway between a lipstick and a gloss, these babies have enough moisture to be easy-wear but enough pigment for definitive colour. No Faustian pact required.