Why doesn't the miter button translate to the scale on miter saws?? What am I missing?

Here are the instructions for using the Miter Saw Blade Calculator: MITER SAW BLADE CALCULATOR: To calculate the needed miter saw blade angle for a simple miter cut, press the Miter Button 3 ; the Miter Angle Icon E will turn on. Then, measure the desired corner and the Digital Angle Finder will automatically calculate and display the exact angle that your saw blade needs to be set to for a perfectly fitted miter joint. Once measured, press the Hold Button 4 to ensure your measurement is accurate as you set your saw blade. To switch from the miter calculator function back to a true angle finder, press the Miter Button 3 again; the Miter Angle Icon E will turn off. NOTE: In order to determine the miter and bevel angles for a compound miter cut, repeat the steps above and look up that measured value in the COMPOUND MITER CONVERSION TABLE chart at the bottom of the page. Hope this helps!