You are starting from scratch when you start a project from the very beginning. Example: "How are you going to build your business?" Reply: "Just like everyone does: starting from scratch."

You start from scratch in cooking when you cook a meal starting with only the smallest food ingredients. Example: "This cake is excellent. Where did you buy it?" Reply: "Actually, my mother made it from scratch." Example: "My father is excellent with cars. He started with spare parts and built this engine from scratch."

When you do or make something using the smallest parts, you start from scratch. Example: "My computer crashed and I lost all of my work." Reply: "That's terrible. What will you do?" Answer: "I'll do it again, starting from scratch."