The miss slammed ORLY peers: Advance Auto Parts plunged 16%, AutoZone tumbled 10%, while suppliers Standard Motor Products, Dorman Products and Motorcar Parts of America also dropped sharpdly.

As usual it was the weather's fault: retailers blamed weak consumer demand at the start of the year on delayed tax refunds- although how that impacted second quarter results is not clear -  and a mild winter that reduced the need to replace some car parts. O'Reilly's Chief Executive Officer Greg Henslee said weak consumer demand continued into the second quarter despite signs of stronger sales earlier this spring according to Bloomberg.

"After exiting the first quarter and entering April on an improved sales trend, we faced a more challenging sales environment than we expected for the remainder of the quarter," Henslee said. "While we are disappointed with our sales results in the first half of the year, we remain confident in the long-term health of our industry."