Overly cautious investors may look at the economic landscape combined with January’s pullback as a reason to hold off on COST stock despite its tempting price. They are key reasons why risk-adverse investors may not want to add Costco to their portfolio at this time, despite the current COST stock discount. In its most recent quarter (reported last December), Costco not only saw big increases in net sales (despite inflation), the company also added another 800,000 paying members, bringing its total to 61.7 million households.