If you are a carpenter, you must be able to make straight cuts with your saw.
If you are an electrician, make sure your wiring works and fires will not haunt you for faulty electrical wiring.
If you are an engineer, make sure the building you design is strong enough.
If you are in ALL other professions, make sure you do things right, or your mistake will be obvious as soon as you finish your work.
If you are a lawyer, you lose your case, your client goes to jail.
If you are a barber, make a crooked cut and you could be cut yourself crookedly by irate customers.
If you are a singer, sing badly and who knows what missiles your audience might throw at you.
If you are a nurse, you must know how to insert proper IVs or at least know your K-sounds when taking blood pressure measurements.
EXCEPT, if you are a DOCTOR.
Their diagnoses do not necessarily be correct. BUT PATIENTS PAY EACH TIME THEY CONSULT A DOCTOR WHETHER THE DIAGNOSIS IS CORRECT! THAT IS A FACT!
Doctors prescribe drugs to patients. Those drugs are based on their diagnoses and which may be correct or not, hence, the patient is buying, and TAKING a drug which may not be correct or not.
BUT PATIENTS STILL PAY THE DOCTOR.
On visit no1, doctor gives diagnosis, prescribe a medicine, patient pays. Patient is asked to come back.
On visit no2, patient reports not improving with the drugs prescribed, patient is given another. Patient pays still.
Maybe patient dies or just dont have money to go back to the doctor. Doctor just takes on another patient.
Doctor, doctor, doctor. The best profession there is. That is why it is so expensive course. Patients may live or may die, just the same they pay.
By the way, I am not a doctor.....