Why do Egyptian hieroglyphic texts provide incomplete evidence for ancient Egyptian pronunciation?

Egyptian hieroglyphic texts provide incomplete evidence for ancient Egyptian pronunciation primarily because the writing system generally omitted vowels. Aside from the semivowels i, y, and w, the script represents only the consonants of words.12

Because the system focused on consonantal roots—a feature common to the Afro-Asiatic language phylum—vowels were not considered necessary for the written record. Consequently, while the script utilized logograms and phonograms to convey meaning and sound, the lack of vowel notation means that the vocalization of the language is not fully reflected in the inscriptions. This divergence between the written script and the spoken language persisted throughout the history of the script, making the reconstruction of ancient pronunciation a complex challenge for scholars.213