Cincinnati, as a city, has a lot to offer. Their university's football team has slowly been on the rise as well. (They're expanding Nippert Stadium to 40,000 seats.)
Yet, nobody seems to want Cincinnati in the conference. Current members of the America Athletic Conference, Gene Smith has basically said Cincinnati could join the Big Ten over his dead body.
There has been speculation Cincinnati could find a home with the Big 12 in the next round of conference expansion, but Mike Davis of Sports Politico isn't a fan of that idea:
Cincinnati’s football stadium is incredibly small for P5 standards. The issue with Nippert Stadium isn’t just its capacity, which is being expanded from 35k to 40k, but the surrounding area. Due to its urban setting, the campus does not have an abundance of space to work with for its athletic facilities.
The state of Texas is notorious for the way its public FBS schools have to compete with each other for state funding and fan support. While the situation in Ohio may not be as bad as things are in Texas, the two closely mirror each other. The University of Cincinnati is located in Ohio and thus in the shadow of The Ohio State University. The Buckeyes have a political and fan support dominance that is unusual for a state as large as Ohio.
The first reason is that Cincinnati is still just one school whose net benefit would be giving WVU a regional away game every other year. That is a very small net gain for the conference as a whole for a very big price tag that would be adding Cincinnati. The advantages of Cincinnati’s proximity to Morgantown will be seen mostly in the non-football sports, but at the same time the rest of the Big 12 will now have to take more Eastern trips to accommodate the Bearcats in all sports as well.
It's a pretty well-reasoned look at Cincinnati's uphill climb in gaining membership to a Power Five conference.
Of course, Cincinnati football will have a chance to show it deserves a seat at the Big Kids' table on September 27th, when the Bearcats come to Ohio Stadium.