Madness constitutes only 15% of all psychiatric diagnoses
The hypothetical column on the left is meant to show that as a result of the stigma of mental illness, most people think that mental illnesses are always severe.
Delirium is a totally reversible state, people with dementia need long term care and can never be more harmless. Lots of people recover from psychosis totally and some retain symptoms.
Only 10% of violent crime in a society is from people with Schizophrenia.