What are the implications of Gatsby's observation that Daisy's voice is full of money?

In chapter seven, Jay Gatsby observes that Daisy's voice is full of money, which implies that she is more concerned about wealth than finding genuine happiness or cultivating a meaningful relationship. Gatsby's quote implies that Daisy Buchanan's primary concern is her financial security and social status.
Unlike Gatsby, who has recently amassed his wealth and lives in West Egg, Daisy comes from old money and is a member of the East Egg social elite. The fact that her voice is full of money not only implies her superficial nature but also alludes to the fact that Gatsby will never be accepted into her social class. As a resident of East Egg, Daisy is above Gatsby's social class and out of his reach. When Gatsby notices that her voice is full of money, his observation implies the impossibility of his endeavor.
Despite the fact that Daisy is more interested in financial security and social status than she is concerned about falling in love, Gatsby is undeterred and continues to pursue her without accepting the reality of the situation. Overall, Gatsby's comment about Daisy's voice implies that he will never win her heart and that her primary concern is maintaining her wealth and social status as an elite East Egg resident.

The quotation tells us an awful lot about Daisy's character. Her voice is "full of money" in the sense that she shares the accent and vocal mannerisms of the old money elite. Every time she opens her mouth you can tell straight away where she's from and what her social status is.
The problem for Gatsby is that this simply demonstrates to him just how unattainable she is. Daisy's very much old money; always has been, always will be. Though Gatsby may be fantastically wealthy, he has no established name; he's a West Egger through and through. Daisy, and the other members of the East Egg social elite, may condescend to come to his lavish parties, but they still look down on him as a nouveau riche upstart, a parvenu who wants to buy his way into high society. Gatsby may have the money, but his voice doesn't and so he'll always remain an outsider to the likes of Daisy Buchanan.