This velar offglide is labialized (pronounced with lip-rounding, like w) after labial consonants, so /bˠiː/ "yellow" is pronounced [bˠwiː].
There are the long thick vowels of "sluggish cream wound curdling spirals" which contrast with the lightly sprung, quick vowels and vivid labial consonants of "Buck Mulligan slit a steaming scone in two and plastered butter over its smoking pith".
In consonant clusters there has been a tendency to replace velar consonants k and g with labial consonants, such as p, b, or m (e.g., Latin ŏcto "eight," Romanian opt; Latin cognatum "relative, kinsman," Romanian cumnat).
Otomanguean languages tend to be characterized by contrastive tones, nasal vowels, mostly open syllables (that is, syllables which end in a vowel or in h or a glottal stop), and a lack of labial consonants (no p, b), though original kw became p in some languages for example, in the Zapotec complex of languages.
In Spanish and Portuguese a following l in Latin often palatalizes labial consonants (p, f ) as well as velars, in initial as well as medial position; e.g., Latin planum becomes Spanish llano 'plain,' Portuguese chão; Latin afflare becomes Spanish hallar 'to find,' Portuguese achar.
/i/ is rounded to [y] before labial consonants.
Short /ɔ/ between two broad consonants is usually a back, e.g. [kl̪ˠɔ̝x] "stone", but it is a centralized adjacent to nasal consonants and labial consonants, e.g. [ən̪ˠˈsˠön̪ˠ] "there", [bˠöɡ] "soft".
For example, both languages contrast "broad" and "slender" consonants, but only at the coronal and dorsal places of articulation; both Scottish Gaelic and Manx have lost the distinction in labial consonants.
Furthermore, weak facial muscles limit lip movement, thus affecting production of labial consonants and rounded vowels.
On the other hand, weakness in the facial muscles restricts their lip movements, and this impedes the production of labial consonants and rounded vowels.
