Any smart employer would look at the reasons.    It is not a black and white scenario as you try to make it out.

For one thing, your words indicate that the employee is faulty based on the first sentence.   Any smart employer would realize that there is more to the story. Not everyone passes judgement based on a single incident.

There is a word that you have never mentioned - "context". You can't make an analogy or clip a statement without looking at the context. Not everything can be accepted at face value, and you have to factor for errors - either in product or judgement. No smart employer would jump to conclusions or build up walls simply because something did not happen "by the books".