Ha! I played the exact same first game!
For example: bills,dills,fills,gills,hills,kills,mills,pills,sills,tills,wills
If the answer is any of these words and you guess the wrong words once, you are unable to guarantee a win (outside of hard mode you could try guessing words to eliminate many letters at once)
I find that constraint to be roughly, if not more, frustrating than commutativity (which doesn’t even apply to subtraction or division!)