The core issues for China are not the same as the core issues for Taiwan and as a result the two sides talk past each other. China and Taiwan have each identified issues that are the most important to them. The central issue for China is the degree of autonomy that Taiwan will have after some form of unification. The key issues for Taiwan have to do with creating conditions now for later talks about unification and the degree of autonomy. Taiwan wants to be considered an equal "political entity" during the negotiations; a time that is considered a "temporary, transitional phenomenon." By not agreeing on a core issue, negotiations fail to make progress.
Strait Talk, Chapter Five: The Issues