Quality Assurance is the art of not upsetting developers (who think you are out to get them), not upsetting management (who think you are delaying the product), not upsetting marketing (who thinks you are making them look bad because they promised that the software would be ready two months ago), not upsetting sales (who passed on the promises from marketing), and not upsetting clients (who want the product yesterday but will sue if it doesn't work).