Some retailers, like Walgreens, report that locking items behind displays to deter shoplifting may not be effective. Walgreens CEO Tim Wentworth recently described theft prevention in stores as an ongoing and challenging struggle.

Walgreens struggled financially last year, reporting an operating loss of $245 million for the quarter, compared to $39 million in the same quarter the previous year, according to Quartz. The company’s decision to lock up products was a response to a 52% increase in stolen inventory, but the method ultimately backfired.

Keeping products under lock and key dissuaded customers from purchasing them, Walgreens said in earnings call.