What do you think allows one to Unlock Lava Bending?

I've always thought about what makes Lavabending is so rare and would be the reason behind some earth benders being able to lava bend while others find uncanny.

I have a few headcanons about, would like know if there are people who think similarly.

1. Lineage

I was wondering if the reason would extremely simple like lineage. Like having one fire bending parents and one earth bending parent. But the only confirmed example of this we have is Bolin. Even that is pretty much entirely speculative since it's never hinted that were even benders. But to be born with a bending ability one should be related to a bender in some way. So this head canon doesn't really have a stable base to stand on.

2. Unique/Non-Traditional Understanding of Earth Bending.

I feel like this one is has more logic behind it. Because both Bolin and Ghazan have a very non traditional way earth bending that involve flips, Acrobatics and staying light on their feet, although they do use traditional earth bending in sometimes. Maybe this fluid bending style is what broadens their horizons to be able to use a new sub-bending.

3. It's just luck 🤞

It's could just be luck, that no amount of training can unlock it if you aren't born with it and if you're born with it you'll be able to use without much effort. So whatever else I've speculated is pretty much nonsense :joy: .

4. All of the above.

Maybe it's a little bit of everything, having the lineage, understanding and being lucky enough to be born with it.