Did you know that people didn't use to read quietly like most of us do today? People used to look at the letters, read them aloud and then hear their own voice and understand their own words. There are texts from the middle ages that talk about people who didn't have to do that to understand and they were considered to have expert reading skills.
It also makes sense if you look at certain writing conventions that lacked all kinds of little helping things we now have to make the silent mode of reading easier. Forexamplespacesbetweenwordsandpunctuation
ifyouarentreadingaloudthetextismuchharderto
understandthiswaybutifyoudoitsnotmuchofachallenge