The Cold Dark Matter model faces many controversies at small scales, as simulations fail to reproduce the observed properties of dark matter (DM) haloes. Since rival DM models differ on their predictions about the structure of DM haloes, understanding their mass distribution is crucial for determining the nature of dark matter. However, only numerical approaches to determining what a hypothesis implies for the mass distribution are possible. Hence, simulations are a crucial part of evaluating DM rival models, as is assessing their reliability. I argue that robustness analysis is not a sufficient criterion for the trustworthiness of cosmological simulations