Ha I knew someone was gonna say it. Longterm, in my case I can say it's a "wound". I know this because I picked my lips until they were raw & they never got the chance to heal.
I didn't really have a dry lip problem, it was just dry that particular day & I who have some mild form of skin picking OCD, just couldn't resist sinking my teeth into the skin & tearing it the dry bits off.
I've thought long & hard about this but it's really the only thing that makes sense. If I leave my lips alone, they'll heal. Take Daniel Miller for example, he left his lips alone for over a year & it healed.this "Oh but he ate lots of fish, the sunlight healed him, Aquaphor healed him, blah blah blah" yes, those may have contributed to some extent but at the end of the day he left his lips alone.
If you keep your lips moist with the right moisturizer which creates an artificial barrier, the crust won't form & the lips would heal faster than if you left the crust alone.
And Longterm I don't mean to shoot at you but you never had ec to begin with.