 Karl Verner is traditionally credited as the first scholar to note the factor governing the distribution of the two outcomes.Verner observed that the apparently unexpected voicing of Proto-Indo-European voiceless stops occurred if they were non-word-initial and if the vowel preceding them carried no stress in Proto-Indo-European.The original location of stress was often retained in Greek and early Sanskrit; in Germanic, though, stress eventually became fixed on the initial (root) syllable of all words.