Simulation coupling is a mean by which already developed tools are reused and run together for the sake of capitalizing on existing endeavours. A main challenge to microscopic simulation coupling is the synchronization of schedulers, which are in charge of ordering internal actions for their respective simulation. To achieve a consistent execution of the overall simulations, simulation coupling must tackle challenges to interoperability and schedulers’ synchronization. In the scope of microscopic simulations, functional coupling objectives can be categorized into different levels from coupled simulations that only exchange aggregated information, to a coupling that highlights novel behaviours. Our goal in this paper is to show that the existing coupling solutions fail to implement the problem where the coupling objective is to combine individual behaviors from diverse microscopic simulations, in order to create new ones. This failure is due to the fact that these solutions consider mi croscopic simulations to be coupled, as whole components with autonomous schedulers instead of a composite set of behaviors. The limitations are shown using the DEVS formalism to describe coupled microscopic simulation under different coupling objectives, with a formalization of constraints induced by shared components.