And of course once you have done it once, inconveniently straddling the bike and groping about, and got it to the correct level, (About half way between the 'Full' and 'Add' marks.) you can put it on its side stand and check it there, memorise where the oil is on the stick and know that for all future checks that is the correct level so you don't have to fart about with the stupid 'Stand the bike upright' nonsense!
Pete