None! But then I don't buy speakers just hoping they will just happen to sound good. If my research suggests (absent an actual in home audition) that the speakers have the characteristics that are important to me in the first place, which are supported by user/professional reviews, I buy them and I will dedicate a considerable amount of time, in some cases years actually, to dial them in by finding the appropriate electronics and carefully setting them up in my room. No small feat I think, and I can always sell them if I can't make them work for me.
Most recent speaker you audited in room and returned? Why did you return it?
Just as the title says, what was the last speaker you got hyped by, purchased and returned subsequently? If you returned it, what did you not like about it in your room? What equipment did you try matching it with?
Hearing about such experiences of unmet expectations could be an interesting topic.