Imagine paying an assassin to kill someone, then the target pays the assassin NOT to kill them

.. How do assassins like this find work, and more importantly how are they still alive?
They should be killed, or blacklisted from ever working again.
My new headcanon is: The Guild of Assassins are KoS and blacklisted, for failure to assassinate the vast majority of their targets, and accepting bribes from targets to not work.
Really very silly. No, I didn't just have a bad experience with them. It just came to mind, haven't used the system in years for good reason.
No suggestion attached.