[en] By considering that the stance held by an individual in a collective decision-making process is intimately related to a quantifiable trait of personality, we study the impact of different sorts of inhomogeneity—namely, polarisation (partisanship) and plurality—of that trait among the population on the final collective stance. It is shown that, although both situations represent forms of diversity in the system, each one is associated with a different type of emergence of consensus that herein we define as a nontrivial collective stance. Specifically, we verify that plurality only relates to a continuous emergence of nontrivial stances, whereas for given degrees of partisanship a discontinuous transition can be observed. That discontinuity implies the existence of a latent heterogeneity in the system; latent in the sense that it is unable to enhance the decrease in the cost of assuming the trivial collective stance over a nontrivial stance. Moreover, in bringing forth the existence of a discontinuous transition—and hence of metastable states of consensus—it is possible to adjust partisanship and heterogeneity in the group so that, by increasing the diversity of the relevant trait to the problem, the system can move from trivial to nontrivial stances. Such effect ultimately assigns to diversity, namely polarisation, a counter-intuitive role of consensus provider. (paper: classical statistical mechanics, equilibrium and non-equilibrium)