It's the first option under each profession that you must be of high enough rank to learn the rare motifs. It makes no difference if you have a dozen points spread out in the profession itself if the rank isn't high enough. That's the option that starts at 1/9 for everyone and goes up to 9/9. I also thought, but could be wrong, that you had to be of the correct rank for BS/Clothing and WW in order to learn a rare motif but maybe it's once you have one of the three at the appropriate rank. I was 9/9 in all before I got my first rare motif so I'm not 100% on that.