The use of iterations allow you to implement partial solutions over time that will ease the problem. Continue the use of iterations until the problem is fully addresses and the learning process is working as desired.
Every training process will develop its own rhythm, which means designers need to find the natural flow of the steps required to produce a successful learning platform. However, if you are new to instructional design, the less you know about a subject, or the more technical the material is, then more than likely, the closer you need to follow the model.
At work, the potter sits before a lump of clay on the wheel. Her mind is on the clay, but she is also aware of sitting between her past experiences and her future prospects. She knows exactly what has and has not worked for her in the past. She has an intimate knowledge of her work, her capabilities, and her markets. As a craftsman, she senses rather than analyzes these things; her knowledge is 'tacit.' All these things are working in her mind as her hands are working the clay. The product that emerges on the wheel is likely to be in the tradition of her past work, but she may break away and embark on a new direction. Even so, the past is no less present, projecting itself into the future. - Henry Mintzberg, Crafting Strategy, Harvard Business Review, July-August 1987, pp. 66-75.