McDonald's is facing slowing sales. Its under $3 value menu shows why

McDonald's rolled out a menu of items under $3 in April and faced challenges almost immediately, CEO Chris Kempczinski said. Bloomberg/Getty Images McDonald's US sales slowed down in the second quarter, the fast food chain said on Tuesday. Its latest value menu is one of the big reasons why, CEO Chris Kempczinski said. McDonald's rolled out its Under $3 menu while cutting back on digital offers, he said. McDonald's tried a new value menu. Customers aren't loving it. The fast-food giant's…