Among the businesses with a category of Accessories, what is the percentage of the business with less than 4 stars?
category of Accessories refers to category_name = 'Accessories'; percentage of the business with less than 4 stars = divide(count(Business.business_id(stars < 4)), count(Business.business_id)) * 100%
SELECT CAST(SUM(CASE WHEN T1.stars < 4 THEN 1 ELSE 0 END) AS REAL) * 100 / COUNT(T1.stars) AS "percentage" FROM Business AS T1 INNER JOIN Business_Categories ON T1.business_id = Business_Categories.business_id INNER JOIN Categories AS T3 ON Business_Categories.category_id = T3.category_id WHERE T3.category_name LIKE 'Accessories'