Faulty recipes: omitted ingredient or unused ingredient

To enhance the quality of your recipes, you need to have someone proof read them and execute the recipe; the second part, you should be there and record everything the testers do or not with your recipe.

To pick up errors and typos in existing recipe, you just need to proof read the recipe and apply whatever experience you have to fix them (for example if a cake recipe seems off with 25 cups of sugar, maybe by looking at the other ingredients it is actually 2.5 cups.

Same kind of analysis for either missing or wrong ingredients; if a cake recipe lists lemon zests but is not in the recipe steps, you need to decide with your own experience one way or the other it it should be used or not.

Anecdotal, there was a TV show (usa or canadian) a while back where they tested recipes from recipe books just by "executing" the recipes literally (no adjustment, no "maybe if we changed that")

There were tons of typos in quantities or missing ingredients or even oven settings (for example recipe forgot to say to turn on the oven) that a novice cook would not see, but a seasoned cook would pick up and adjust automatically.