Your right. For many people on here it is a complete mystery as to how this condition started, and the guesses may just be way off base.
But for me it was VERY clear.
I was a lip biter for many years. And once in awhile I would bite my lips to much or too hard and I would create a wound. And this wound would be red/raw/irritated EXACTLY how our skin is under the crust/buildup. The difference is that it would just heal very quickly.
So during final exams last year I noticed I was biting my lips a lot, mostly due to the intense/long studying. And after I was done with finals I had that same red/raw/irritated wound on my lips in the EXACT places I bite. Which is all around the vermilion border. The only difference is that it wouldnt heal and I had this scab-like growth that you know all too well.
So before I read anything about Exfoliative Cheilitis, or even knew that EC existed, I assumed that this was because of biting, and my lips werent healing properly.
For awhile I just moisturized them and left them alone and they didnt really change much, I actually thought they were getting better at one point.
But then I began constantly rubbing off the buildup and only after that did it start getting worse and spreading down my lip.
So sorry for the long ass post, but my point is that I am positive about when and how I got it. Whether it be fibroblasts due to constant trauma or something else, I know that my case has something to do with trauma/wound/biting. And all these months later, all of my tests and treatments point to that being by far the most plausible hypothesis.
Even a few doctors who said it was impossible at first, now believe it is a wound, based on everything that Ive done.
In that sense I actually feel a bit lucky because its better than just waking up with it one day and having no clue what happened.
The only reason I ever got away from this though is that all of these dumb ass dermatologists kept telling me its impossible, except for the first derm. I ever spoke to about it, which is the only one i am now still talking to. (the family friend who said she has seen this before). I should have just listened to her all along...