An ability I possess that has always come naturally is patience. I don't rush anything that's worth doing right and always have a plan of action before I start a job. 
Patience serves me well because sometimes jobs can be tedious or require more thoughtful preparation and planning. At the end of the day I know the results of my efforts need to match or exceed my clients expectations. If I didn't have patience my work would suffer and I doubt people would refer my craftsmanship.