Why do Muslim women think they only way to dress "modestly" is by covering their entire body with fabric?

Beouse that is what they have been told since they were born. What your sense of modestly is is becouse of what you grow up being told and am used to. I believe that you don't need to cover your whole body in order to be modest, but that is because I grew up believing that their is nothing wrong with going around in a pair of shorts(as long as they are not to short) and a tshirt.