MINNEAPOLIS — Best Buy said Thursday it had disappointing sales during the holiday shopping season, raising concerns about the consumer electronic retailer’s ability to turn around its business.

The holiday season, which runs from November through December, is a critical period for retailers because it can account for up to 40 percent of their annual revenue. But this past season was marked by weak consumer spending and heavy sales promotions by retailers.

Best Buy was struggling even before the holiday season because of increased competition from online stores and discounters. But under CEO Hubert Joly, Best Buy started a turnaround strategy that included revamping merchandise, training employees and cutting costs.