My homemade buttercream sucks

So I made buttercream yesterday again for the second time. It was awful. I don’t know if it’s supposed to taste like this or not. I don’t think it is. I followed a recipe online and it tasted like butter and sugar and vanilla. But it just was nasty. I could taste the butter so o added more sugar. It didn’t help. Can someone give advice for making frosting? I really want to make my own