What is the proportion of action movies directors who are called 'box office success paradox'?
'box office success paradox' means average revenue exceeds their quality; The proportion can be computed by [(avg_revenue > d_quality) / ()] * 100%
SELECT CAST(SUM(IIF(T2.avg_revenue > T2.d_quality, 1, 0)) AS REAL) * 100 / COUNT(T1.movieid) FROM movies2directors AS T1 INNER JOIN directors AS T2 ON T1.directorid = T2.directorid WHERE T1.genre = 'Action'