Starter discard?

I frequently see reference to using sourdough starter discard in recipes. I don’t really get it though because I never throw away starter. What’s up with that?

Some people build in excess and when it comes to feeding their starter to prep for the next bake they have too much so they discard some before feeding. Hence all the recipes to use up the discard. With careful management this need not be an issue. If I wish to use starter in recipes, besides for a bread, I have to purposefully build “discard”. Adds nice flavour to other baked goods.