Glue Data Quality producing empty files after applying a conditional router

I am using Data Quality to evaluate the dataset and I am routing the failed rules and failed records. But when i check the s3 bucket for the failed records i am seeing empty files along with the failed records. The routing condition is using a regex match for records having DataQualityEvaluationResult = Failed. So i am not sure why glue is outputting empty files in the s3 bucket. Any suggestion on how to correct this would be greatly appreciated.