Correctly identifying the structure and competitive dynamics of the industry you are proposing to enter will create a good general point of reference for judging whether you should enter it or not. If the general industry profile does not appear attractive to you, and you are planning to offer value propositions that have close industry substitutes, then this may be an important signal that your proposed venture may need to be reconsidered. But if the industry profile looks attractive, then this could be a sign that you are on to something.
A fantastic tool to analyze an industry that serves a Defined Existing Market is Porter’s Five Forces Model. Michael Porter is a professor at Harvard Business School and published this strategy model in his seminal work, Competitive Strategy. Porter’s model is powerful. It demonstrates how an industry’s attractiveness to either its current competitors or a new entrant is an amalgam of disparate, and sometimes contradictory, factors.
To help determine if your business idea will be worth the investment of time, money and energy, you will conduct two sequential analyses using the Five Forces Model. The first Five Forces analysis will be of the overall industry that you are contemplating to enter. The second Five Forces analysis will be of the particular market segment(s) you would be choosing to serve with your Value Proposition(s).
The figure below illustrates how Porter’s model works by focusing on the five forces that shape competition within an industry: 1) the risk of entry by potential competitors, 2) the intensity of the rivalry among established companies within an industry, 3) the bargaining power of suppliers, 4) the bargaining power of buyers, and 5) the similarity of substitutes to an industry’s value propositions.
The main point of Porter’s Five Forces Model is as follows. The stronger that one of the five competitive forces becomes, the greater the overall competitive rivalry becomes within the industry. The more intense the competitive rivalry becomes, the harder it is for ventures within the industry to raise prices or maintain high prices to reap greater profits. The less in average profits that a firm in the industry is able to earn, the more intense the rivalry for customer demand is among the industry’s rival competitors.
The opposite is true also. The weaker that one of the five competitive forces becomes, the less intense the overall competitive rivalry among the industry’s firms is. If rivalry amongst the industry’s firms decreases, the easier it becomes for the industry’s competitors to raise either raise prices or reduce their cost structure (by lowering their value propositions’ quality) and ultimately earn higher profits. The higher the average level of industry profits, the less intense the rivalry for customer demand will be among the industry’s rival competitors.
The importance of each of the five forces is situationally dependent upon the unique facts and circumstances of each industry. For example, the overall threat of new market entrants might be insignificant in determining whether an entrepreneur wants to enter an industry in its growth phase, but it may be a paramount factor in a mature industry.
I developed another diagram (below) to show how the five forces within Porter’s model interact with each other. As you can see, four of the forces (risk of entry by potential competitors, bargaining power of suppliers, bargaining power of buyers, and threat of new entrants) each act upon the fifth force – the intensity of rivalry among the industry’s competitors. This means that if the bargaining power an industry’s buyers increases, the intensity of rivalry among industry competitors will increase. This causal relationship works in only one direction – a change in any of the forces ultimately either increases or decreases the intensity of rivalry among the industry’s competitors. Therefore a change in the intensity of rivalry will not cause change in one of the other four forces.
 Charles W. L. Hill and Gareth R. Jones, Strategic Management Theory, Eighth Edition, Houghton Mifflin Company, pg. 45, 2008.