system
Given the following post, respond as if you're commenting on Reddit:
human
What determines the axis of a black hole's accretion disk? Is its orientation always stable?
gpt
The accretion disc of any collapsing dust cloud emerges from the shape of the cloud and the initial velocities of the particles. As opposing momentums cancel and similar momentums combine, the cloud gradually develops a spin which reinforces itself by first accelerating the surrounding orbiting particles into having a complementary momentum, and then pulling them into an impact which adds to the angular momentum of the disc.

After a stellar object (and an accretion disc) have built up this angular momentum, its orientation is very resistant to being changed, exactly like a gyroscope's (and why we put rifling in our guns to make bullets spin when they are shot out). The orientation can change, though, similarly to how there's a precession in the Earth's rotation. It just takes enormous forces to do so.