why cant you use the same name for two parts?

while wait() do
	game.Workspace.qwe.Position = game.Workspace.qwe.Position + Vector3.new(0,.1,0)
end

while wait() do
	game.Workspace:FindFirstChild("qwe").Position = game.Workspace:FindFirstChild("qwe").Position + Vector3.new(0,.1,0)
end

there are two parts in the workspace called 'qwe'. the scripts above are teststo see if they would both start floating higher, but apparently, you cant use the same name for multiple parts. is t impossible to use the same name, or is there something im missing?