Muon decays are almost always written as $$\mu^{-} \rightarrow e^{-}+ \bar{v_e} +v_{\mu}.$$$$\mu^- \rightarrow e^-+ \bar\nu_e +\nu_\mu.$$
The reason given on wikipedia is that one of the product neutrinos of muon decay must be a muon-type neutrino and the other an electron-type antineutrino due to conservation of leptonic family numbers.
Does this mean that muons can't decay into quarks plus a muon-type neutrino, which can be lighter particles than the muons itself and with electric charge added up to -1? If they can't, why?
