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Major driving faults
I don't think this would be counted as a major fault or even a minor fault. On the other hand, this will be seen as good observation skills as you would have prevented an accident from happening.
However if you saw that people were walking towards a foot crossing and you miscalculated the time by which they would step on the crossing and continued driving, then this could result in a major driving fault as your observations would be negatively perceived because of your wrong judgement.