Short term memory

So less than two weeks ago I decided to draw profile views since I never do those and now I'm getting pretty good at them...so then I'm like I havent drawn 3/4 in awhile lets do that! Holy crap it's like I forgot how to draw 3/4 and full frontal positions lol wtf. Anyways after awhile i picked it back up but jees :( i wish once you learn how to draw something you wouldn't forget >_<. Quick >10 min of my ninja!