Sales for the signature basketball shoe of NBA Golden State Warriors superstar Stephen Curry have been below expectations, Under Armour chief executive officer Kevin Plank said Thursday. Curry, the NBA's Most Valuable Player in the 2014-15 and 2015-16 campaigns, has the league's top-selling jersey and has sparked the Warriors to an NBA crown in 2015 and a record 73-win season in 2015-16 before losing to Cleveland in the NBA Finals.