Lips have almost no sebaceous glands, so they cannot produce the oil that keeps the rest of your skin supple. Everything about lip care follows from that one anatomical fact.
Lip skin is thin, has no sweat glands and almost no oil glands, and it has no protective outer layer worth the name. It cannot moisturise itself and it cannot hold water. Everything it has, it got from somewhere else — which is why the whole category is occlusives: waxes and butters that sit on top and slow the loss.
Hemp seed oil is a good carrier in a balm because it absorbs into what little skin there is while the waxes do the sealing. It is not, on its own, enough — a pure oil on lips is gone in ten minutes.
The cooling tingle in a medicated balm is mild irritation. It feels like relief and it dries lips further, which is why the balm gets reapplied, which is why the tin empties in a fortnight. If a balm makes you want it again within the hour, suspect the balm.
Flavouring has the same problem with an extra one attached: a flavoured balm invites licking, and saliva evaporating off lips takes more water with it than it delivered.
The version that works is unglamorous: an unflavoured, unscented balm with a wax, a butter and an oil, applied before bed and before going out in the cold rather than reactively when lips already hurt.
Not chemically. What happens is a cycle: an irritating balm dries lips, dry lips want balm. Switch to an unflavoured one and the frequency drops within a week, which is the tell.
Lips burn easily and have no melanin to speak of, so for skiing, sailing or a long summer outdoors, yes. For daily winter use it matters much less than what else is in the tin.
That is usually not simple dryness — it is often fungal or bacterial, or related to a deficiency, and it does not respond to balm. Worth a pharmacist rather than a fourth tin.