AutoZone and O'Reilly are quality businesses worth a premium because stronger auto parts retailers keep taking share from weaker rivals. The industry was once highly fragmented, with the top five holding under 5% combined; today large operators such as AutoZone and O'Reilly control about 25% and keep outperforming. Quality stocks look expensive only in absolute terms, so business quality matters more than valuation, though even the best companies should not be overpaid for. x.comÂ

