Depends on which artist, the vocal style, and the language. Sometimes I don't care about the lyrics, If I understand 1-2 words, and there aren't much lyrics, I think I've get the point of the actual track. But when there is a lot of lyrics, and I don't understand a single word, and there are no lyrics anywhere, it's a little bit frustrating. My suggestion is when there are a lots of lyrics, with non-stop talking/vocals, I think it's better when it's clear, and understandable. When there are two-three words, and I know the title of the track, and the aesthetics of the artists, it's not problem it's distorted/delayed/reverbed/modulated to the extreme level. Also, If it's not talking, but screaming/deathgrunt/anything harsher vocal, it's hard to make lyrics comprehensible, due it's mouth position of these technics.. and when it's also distorted, nobody will understand a single word. Even the artist after the recording.