Fig 1: Confirmation bias in science
With a given set of topics followed by users within Quora, it would seem that finding an audience is limited to those who are explicitly following a topic. This would seem antagonistic to Quora's intention to allow content to find an audience.
The power of blogging on the web is that new topics are marketed via channels to people who have latent interest but have not explicit interest. For example I may find a topic like Metamaterials
or the impact of Graphene interesting but haven't ever heard of the topic. Breaking into a new audience graph based on latent interest is the core of the author-audience discovery problem. This would allow interesting knowledge to cross into new audiences beyond its explicitly defined audience.
Solving the problem of having an audience means Quora would have to solve the problem of distributing information not only to users who were explicitly interested in a topic but also latently interested in information.
In this regard, Twitter does a better job, which uses following people as the qualifer of latent interest, since latent interest is a superset of directed interest.
The power of Quora
as a platform for an audience also depends upon what topics are being defined on Quora. Which currently makes Quora awful for niche topics that have an audience found elsewhere.
The key to driving these audiences onto Quora, its growth as a platform and writer incentivisation will therefore depend upon how Quora integrates with the open web.