Why did the skill of writing disappear from Mycenaean society?

After the Dorians attacked, the Mycenaean people fled to the hills. Concerned primarily with survival, the Mycenaeans did not continue to use the skill of writing.
After the Mycenaeans were destroyed, no written records were transferred because the Dorians had their own form of writing.
After the Minoans were destroyed, no written records were transferred, and no survivors were available to teach the Mycenaean people how to write.
After the Mycenaeans were attacked, no written records were preserved, and the skill of writing remained with the Egyptians.