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Recent experimental signals have led to a revival of tetraquarks, thehypothetical $q^2\bar{q}^2$ hadronic states proposed by Jaffe in 1976 toexplain the light scalar mesons. Mesonic structures with exotic quantum numbershave indeed been observed recently, though a controversy persists whether theseare true resonances and not merely kinematical threshold enhancements, orotherwise states not of a true $q^2\bar{q}^2$ nature. Moreover, puzzlingnon-exotic mesons are also often claimed to have a tetraquark configuration.However, the corresponding model calculations are practically always carriedout in pure and static bound-state approaches, ignoring completely the couplingto asymptotic two-meson states and unitarity, especially the dynamical effectsthereof. In this short paper we argue that such static predictions of realtetraquark masses are highly unreliable and provide little evidence of the veryexistence of such states.

Why static bound-state calculations of tetraquarks should be met with scepticism