More accurate free energy methods should generally lead to better labelling of potentially synthesisable materials. This will allow one to avoid both false positives, where predicted stable phase only exists at very low temperature, and false negatives where a phase is deemed unstable either locally or globally, but is in fact stable at finite temperature. Phases that are locally unstable at athermal conditions, but locally stable at ambient conditions, can be avoided by employing an appropriate anharmonic description of the phonon dispersion and free energy of the system.