Stage 4 liver failure means that the person who has the stage 4 liver failure is at the end stage of liver failure.
When you get to the point of stage 4 liver failure it's a pretty serious thing and the liver cannot heal and there's no way to fix the failed liver.
That is unless you're able to get a liver transplant in time before you die of the liver failure.
Some people with Stage 4 liver failure live 10 to 15 years which is rare while other people with Stage 4 liver failure may only live for 2 to 6 years after they get diagnosed with the stage 4 liver failure.
If you do have stage 4 liver failure then try to get a liver transplant if that is what you want but be prepared to pass away sometime because sometimes it can be hard to get a liver transplant in a timely manner.