When a player is upgraded to the next tier, they will receive a number of upgrades to their attributes depending on their position and the tier that they are upgrading to. This is shown on the national teams player info page with the numbers with + signs before them in green next to attributes. These are the bonuses that will be applied to attributes if the next upgrade from one tier to another is paid for. As a player’s dribble attribute goes up they can also gain access to new skill moves  that they did not have access to before.