Under such circumstances, while disciples of the various Immortal Sects who violate the sect rules also face harsh consequences, it rarely endangers their lives.
Because of the unstable situation and the great demand for strength in numerous wars, it is not allowed for those sects to inflict too much damage upon their own power.
The more disciples die, the more it equates to voluntarily weakening one's own strength, exposing one's vulnerabilities to the enemy.
With hungry wolves nearby, showing weakness would only lead the Wolf Pack to swarm and shred you into pieces before feasting on your remains.
As long as one does not wish to die, then each Immortal Sect would only actively strengthen its own power, absolutely refraining from weakening it.
The relationship between a sect and its disciples is mutually reinforcing, resulting in a balanced equilibrium.