The hard part is the "when their stories are found to be factually incorrect". If you have that solved that then you don't need the rest. Otherwise you would just game the system by retracting posts irregularly.
Sources should be critically evaluated constantly, but sources that are usually more off should be treated differently than sources that are usually more on.
But that's the point. There seems to be a large number of people and organizations (including the US President) who are NEVER interested in issuing retractions or admitting fault - when something is pointed out as factually false, they just repeat the falsehood louder even when there is stuff like audio or video evidence that directly refutes it.