Experience: makes the difference between thinking something and knowing it. It's hard to appreciate or explain the value of experience until you've got it. To want-it-now young-'uns the notion of building an arsenal of experience through years of practice and applied, conscious learning is repellent and unnecessary, but it's the most valuable tool in the box.
Ability: there's no such thing as 'natural talent' on a motorcycle - bikes haven't been around for long enough for nature to recognise a need to hardwire-in the ability to ride one. Ability, be it machine
control or roadcraft, comes from a combination of enthusiasm and an applied, conscious desire to learn and improve.
Confidence: knowing you've got the skills and ability to deal with anything frees up valuable brain capacity. Confidence removes much of the stress and worry of riding on the road, it allows you to relax and focus more clearly. The world around you happens more slowly when you've got nothing to worry about (see also 'Arrogance').
Arrogance: a surplus of confidence can lead to this, but it's not such a bad thing in small doses - as long as you don't get carried away. But don't let arrogance be a barrier to learning more, and don't dismiss others as a source of further knowledge and skills. Most people can teach someone something worthwhile.