I think it's hard to have an consistant level of quality if you release as much material as Ayu does. So you tend to repeat yourself. And maybe the casual listener thinks "Mmh I've heard this before. And since I already have an Ayu record, I won't buy this one." For me I actually only buy Albums of Ayu. But as a Fan I've bought all of them and I probably will buy the new ones she puts out anyway, no matter if I like the singles or not. I prefer most Album tracks over singles. I don't think it's that bad that her sales are dropping. It happens. I don't really care. She's earned enough money and is at a stage in her career where she can do it only for the fans.
