South Korean credit appraisers have inflated ratings of local companies to secure profit sources, analysts said Monday, raising concerns that they may overlook potential corporate failure. Three credit appraisers here, -- Korea Ratings Co., NICE Investors Service Co. and Korea Investors Service Co. -- have rated local companies on average six grades up compared with corresponding assessments by three global players -- Moody\'s Investors Service Inc., Standard & Poor\'s (S&P) and Fitch Ratings Inc., according to the Korea Center for International Finance (KCIF).