Sometimes in order for you to understand why something is good news, you need to understand the bad news. Sometimes people, even including Christians, don’t fully realize why the Gospel is literally The Good News.
Your sin offends God. That is what you need to realize before you are saved, because you need to know what you’re being saved from.
It’s like being sick without knowing it. You don’t know what good a cure will do for you if you don’t realize and acknowledge that you’re sick.