You never have to erase not matter what medium you use. It’s a little like never having to say you are sorry. You can still revise and correct your painting, but it does not mean having to remove the pigment from the paper or canvas. You can just paint over whatever needs revision.
Lately, between acrylic paintings, I paint with coffee on paper. It is a way to practrice painting without much of an investment of either time or money.
Today I painted a portrait and realized the eyes were too small. So I just went in and made them larger. Just like that!
Realizing you never have to erase is a liberating feeling.