Snap (fka Snapchat) (PRIVATE: CHAT) is poised to become one of the most sought after IPO’s of the year, with the company valued at $25+ billion.Nonetheless, I still have lingering doubts that Snap can become the “next Facebook” due to some of the characteristics of the app itself. Many incorrectly characterize the Snap’s demographic as “millennials,” which is not exactly true as the average millennial is now over 30 years of age, with the oldest already beginning to enter their 40’s.In reality, the bulk of Snap users were born between 1992 and 2004 and the app's primary catering to the under-25 demographic is not attractive for prospective advertisers. The 13-24 demographic has little collective purchasing power and limits the revenue potential for Snap and also the type of ads they can run.Facebook (FB), on the other hand, has enough pull among older demographics and has been in use for long enough to keep its user base around as it ages (and therefore becomes wealthier).Snap has a separate messaging primitive from Facebook in which photo/text-mixed images appear for short durations after it’s been sent. And the app hasn’t been monetized to a point where the company is profitable or generating the revenue to be expected from a user base of its size. Moreover, if Snap were to monetize its use for a fee, it’s substantially young user base would likely disassociate from the app, and is hence unlikely.Snap will therefore likely need to develop multiple streams of revenue aside from advertising, which is likely to disappoint. The company has already begun to shape itself into more of a multimedia company, but is in the early stages.For now, Snap’s value proposition and further clarity in how it plans to monetize its user base remains to be seen.