Doctors, Lawyers, Accountants, Computer Programmers.
I have noticed that when your Doctor tells you to do something, you often do it. Sometimes you might ask a second opinion, but generally you listen to and take their advice.
When you lawyer tells you to change a contract, you usually listen. Maybe you take a chance, but you never go outright against your lawyers advice.
Accountants generally give you information that saves you tax, and prevents you breaking the law. You don't go against their advice, and the accountant is not allowed to go against the tax law as a code of conduct.
Then we get computer programmers. For some reason, the customer thinks they can demand anything. It might be as simple as a stupid interface change that would make a product hard to use. Customers, who are rare, but also benefit the most, listen to their experts - even the computer programmers.