A patient comes in with a broken tooth. It's a tooth that has been filled several times before and now it has lost a cusp.
One way of handling that situation is to say “I'll fix that” and then refill the tooth. The problem with that is that, if the tooth breaks again, you own it. The patient thinks your filling was badly done and you must do it over for free.
A smart dentist transfers the risk. Prior to starting work they inform the patient that the tooth is weak and if it is filled again then there is a high probability that it will break again. They tell the patient that there is a stronger alternative — a crown.
Then, if the patient chooses the filling they know they were taking a risk. They don't blame the dentist and they don't expect the work done over for free.