  The intrinsic presence of ghosts in the symmetric teleparallel framework is
elucidated. We illustrate our general arguments in $f(\mathbb{Q})$ theories by
studying perturbations in the three inequivalent spatially flat cosmologies.
Two of these branches exhibit reduced linear spectra, signalling they are
infinitely strongly coupled. For the remaining branch we unveil the presence of
seven gravitational degrees of freedom and show that at least one of them is a
ghost. Our results rule out $f(\mathbb{Q})$ cosmologies and clarify the number
of propagating degrees of freedom in these theories.
