With listening text is just there in front of you can read at your own pace but with listening it's a different type of interaction the written word also has a standardized spelling system which everyone more or less follows. English is an extremely diverse language in which there are many equally valid versions of the spoken word so that's why in listening is more difficult than reading and maybe the fact that it's transient like that is one of the reasons why listening is not done so much in the classroom or hasn't been done traditionally.