We can only say: both yes and no! Some beers have minimal foam or no foam at all, and they taste delicious. For example, Imperial stout, Barleywine, or some sour beers have a minimal foam, while also having rich aromas and flavors. Hence, the foam does not determine the quality of the beer. Still, if some beer is supposed to have a strong foam, such as lager or Weizen, and it, on the contrary, doesn’t have a stable one, this can indicate that something may be wrong with it.