Price increases, that's the answer. Whilst I've begun to buy some not-too-cheap stuff from other manufacturers, I'd still spontaneously buy Warhammer, Lotr and even 40k and Specialist Games miniatures if it wasn't for the damnably high price levels of GW's products. The larger armies of today's 8th edition are just fine, mainly because wargames look better with more miniatures, but the price increases have in retrospect been a serious dampener on both my and my friends' purchases.
Nowadays we rarely buy something spontaneously, but instead almost always plan our purchases and order them from a Swedish retailer webstore. This seem a serious long-term problem for Games Workshop, since we cannot be the only ones who have ceased with spontaneous purchases. Once I bought the then-newly released Balin and Khazâd Guards box almost on impulse, along with some Lotr Dwarf warrior blisters, but such buying is unheard of these days.