What was a major problem with the trait approach to leadership?

What was a major problem with the trait approach to leadership?

1. The results were too innovative and thus were not taken seriously at the time.
2. The results were too inconsistent and thus not very practical.
3. The results were not very inspiring and thus ignored.
4.  The results were found to be too pessimistic and thus were dismissed as useless. 
5. The results were too workshipful of certain leaders and thus were dismissed as irrelevant.