@Riot Question Regarding Goals With Balance

So i got to thinking and was looking at winrates, we have about 60 or so champs with above 50% winrates right now, most of them aren't above 52% and so i was curious, if a champion consistently has a 50% winrate and doesn't fluctuate that much, is that considered balanced and if so does that mean champions with 50% winrates that don't fluctuate never get changed because they are considered "balanced"

I guess i'm just asking if your goal is to one day make every champion have a solid 50% winrate that doesn't fluctuate to much.