I believe Motta wanted them to. I think this is his preferred / idea of opening up defenses. Taking someone on in a 1:1 duel can be a way of losing possession as well so I think most times the players are not up for the risk of losing the ball. The tactics need to be very clear that someone supports behind in case the engaging winger loses the ball. But you're right, Conceicao probably has a lot higher success rate in take ons than Mbangula, Yildiz, Weah and Nico. Nico seems to have lost all confidence and I cant remember seeing him take on someone since he scored a solo goal running from a defensive position.
