The graphic setting “Master Quality” has the horrible habits to set back to the default option, no matter of what was you choice.
for example i want that option to Medium quality, but no matter what it will go back to “High” that is the default one, soon or later.
at first i didn’t notice it because if you change this in the options you will see your choice there, but the game will change it anyway without changing also the label on the window.