I use the word "priorities" more often than I use it's singular form: priority. You wouldn't think it, but the words really have two different meanings. Priority means "highest in importance." There can't be more than one thing that is highest in importance. So we use the word Priorities to mean "important things."
Priority, when made plural, loses its meaning.
I should have but one priority.
Psalm 27:4 One thing I ask, and this one thing I seek; that I may dwell in the house of the Lord all the days of my life, to gaze upon the beauty of the Lord and seek him in his temple.