Are the barriers to entry in the automobile manufacturing industry low, moderate, or high? Explain your answer and then Tesla's success. Is the intensity of rivalry in the fast-food industry low, moderate, or high? Explain. Is the threat of substitutes low, moderate, or high in the U.S. airline industry? Explain. Must all industries proceed through each industry life cycle stage? Why or why not? Explain. What are the limitations of Porter's five forces model? Given these limitations, is it helpful or not? Explain. What is the purpose of conducting Michael Porter's five forces analysis? Describe the five forces that this analysis focuses on.