If you are professional you know what kind of potential problems might happen and you know what are reasonable possible approaches to handle it.
If security of your piece of software relies on default values of some settings I would reasonably expect you to have automated tests to verify that these settings have correct values.
Next time you hire an electrician who causes damage to your house because he did not follow procedure to wire it correctly, will you be still calling him "professional" because he quickly removed the short?