True to form, my fiance and I both spend a lot of time filling in the gaps between heavier adult fiction offerings, many of which are SF/F, with YA fantasy novels, which are universally easier to get into and quick to develop. I can easily remember a time when this wasn't the case... I started reading adult fantasy at a fairly young age, conquering LotR in the 4th grade, and my tendency, by high school, was to seek out increasingly more rich and complex stories. In retrospect, I don't think I considered YA a viable alternative until Harry Potter.