What happened Shares of nutrition supplement maker BellRing Brands (NYSE: BRBR) fell sharply at the open on Friday, dropping as much as 17% in the first hour of trading. Distribution gains in a hot product category were key tailwinds, with pricing actions to help offset the impacts of inflation also showing up as a net benefit. But just the mere mention of supply chain troubles, especially when a company states that the issue is leading to "low inventories and missed sales," is enough to put investors in a selling mood.