CarMax Inc. (KMX) shares plummeted 5.33% during intraday trading on Wednesday, reversing earlier pre-market gains following the release of its fiscal first-quarter results.

The used-car retailer reported net sales and operating revenues of $8.01 billion, beating Wall Street estimates, but its net income fell to $185.6 million from $210.4 million a year earlier. Total gross profit declined 4.4% to $854.4 million, which the company attributed to price cuts implemented to stimulate sales.

Adding to investor concerns, new CEO Keith Barr provided candid remarks on an analyst call, stating that "our core operations are not yet fast and efficient enough" and that "our costs remain too high." The stock, which had risen in pre-market trading on the revenue beat, turned sharply lower intraday as the market focused on the declining profitability and the CEO's acknowledgment of significant operational challenges.