Mental institutions often are veiled with a positive slogan which misinforms customers. These customers are lured into undertaking the "mental" psycological processes.
See school or nursing home.
Other institutions force unwilling hospital patients into their mental facilities. These unlucky patients are sent to a different kind of mental institution called an asylum, which is harsher than a school but with more if not equal brainwashing strength. Different types of similar mental institutions include crisis stabilization, open units, medium-term, juvenile wards, long term care facilities or halfway houses.
Sometimes corrupt government leaders of authoritative countries use mental institutions to punish people they simply don't like. The president of an authoritative country might banish a senator he ran against. The senator would have to go into an psychiatric hospital to get the "treatment" that he or she needed. This is a way for government leaders to get rid of people they don't like.
Conclusion: Mental institution=bad
You get the point.