In Healthcare (and personally) we (I) use the philosophy of "informed consent". That means the person offering the service is obligated to give all the pros AND CONS of the service, object, treatment.
If you are selling a house, you should disclose it was built on a former toxic waste dump, not leave me to google searching the property and street to discover it. If you are selling a particular surgical procedure in a high risk patient you better tell me that 20% end up on permanent dialysis as a complication. If you are selling a an animal, you should represent it accurately including known longevity and genetic issues specific to the breed.
Thats my personal philosophy and expectation. Needless to say, people disappoint me a lot. Including in healthcare.