If the aspect ratio of your device is different from the Width and Height in game.project then the fixed fit will make sure that the area covered by Width x Height will fit inside the display of your device. This means that you either have additional space to the left and right or top and bottom. Like in the screenshots here:
If you want to position something in the lower left corner you will have better luck using a GUI component, since the GUI always covers the entire screen, regardless of aspect ratio.