HOW MUCH DO NON-AUDIO FACTORS INFLUENCE YOUR AUDIO PURCHASES?

I think most audiophiles would like to think it's all about the sound, but for me there's often many factors not related specifically to sound quality, that play a big part when deciding what audio component to buy.  Perceived build quality, brand name reputation, specs, even things mostly related to appearance can have a big influence.  I have for years, pursued matched, one-brand systems and seemingly can not be truly content with my two-channel rig otherwise, regardless of the performance or build quality of specific components.  I sometimes think the whole process is, for me, more an exercise in obsessive behavior than a rational pursuit of a logical outcome.  So how about you?   Any tales of audiophilia nervosa  you'd be willing to share?