The intention is to guide opposition play to the wing. There, it would mean cutting opposition formation by half. You would need to cross the ball well, or have quality players on the same wavelength to combine to penetrate through the compact low block in the middle. The defending has more numbers in this situation
Remember the game we lost against Mourinho Man U in first season? Sissoko had the beating of that Italian defender on their left wing, but we couldn't approach centrally with them having so many bodies and good penalty box defenders, and Sissoko couldn't cross the ball well. Man for man we won, but tactically they had us running in circle.