[Hanger]

Because one function stores the float and the other manipulates. You can easily modify that to suit your need. This, suppose, is just the way PAWN works.

Code:

stock Float:GetHP(playerid) {
new Float:health;
GetPlayerHealth(playerid, health);
return _:health;
}

// Now you can do your simplified action using GetHP.
//Not sure about tagging the Float: