Once upon a time in a services economy

[timelets]

http://www.bbc.com/news/world-europe-41930177

Toxicology tests suggest a German former nurse murdered at least 100 people at two hospitals where he worked, prosecutors say.
Detectives believe Niels Hoegel, who is already serving a life sentence for two murders, systematically administered fatal doses of heart medication to people in his care.
He wanted to impress colleagues by resuscitating them but many died.
Hoegl said that each time someone had died, he had resolved never to do it again but his determination would then slowly fade.

This is a good example of how you can't undo a service even if it leads to deadly consequences. Due to high information costs, a service institution substitutes verification with a cheaper trust mechanism.