Following one of Warren Buffett's core investing principles could have kept many investors from getting burned by this particular money-losing stock.The swoon in Beyond Meat's (BYND 1.66%) stock in recent years has been dramatic. The stock that topped $230 per share soon after its 2019 initial public offering (IPO) slumped steeply in 2021 and 2022. That steady decline has continued, and in recent weeks, it dipped below$1 per share.That extended drop occurred against a backdrop of falling popularity for the ...