BCG Matrix

The BCG matrix (also known as B-Box, BCG analysis, BCG-matrix, Boston Box, Boston Matrix, Boston Consulting Group analysis, portfolio diagram) is a chart, or matrix, created by Bruce Henderson for the Boston Consulting Group in 1970 as a tool for corporations that will help them analyze their business units or products. By using the BCG matrix it will help companies to allocate their resources and is often used as an analytical tool in brands marketing, product management, strategic management and portfolio analysis. 

In order to use the chart the analyst creates a scatter graph so as to rank the business units or products based on their market share and growth rates. There are four main categories.

1. Cash cows are units or products with high market share but slow growth. These are usually the products that generate a lot of revenue while not demanding much in terms of their maintenance for the company. They are regarded as boring, but every company would be happy to have a number of them. Their only purpose is to be "milked" with as little investment into them as possible. 
2. Dogs, or sometimes called pets, are products with low market share in a mature, slow growing market. They usually only "break even", generating enough cash to keep the current market share. It is a good line of products in that it has a social benefit of providing a jobs and possible synergies with other products, but generally they are considered worthless since there is no extra revenue generated by them. Most of the companies would prefer selling them off.
3. Question marks, or problem children, are rapid growers and in doing so consumer large amounts of cash. They have low market share and do not generate much in return. The end result is large net cash consumption. They have a potential to become a star, and eventually cash cow. If it doesn't suceed in becoming a market leader after some time (usually measured in years) it will slide down to a rank of dog. Question marks have to be analyzed carefully so as to determine are they worth the investement.
4. Stars are products with high market shares in a fast growing industry. Everybody hopes that a star will be a cash cow. Sustaining the high market share may require further investments, but it just might be worth it in order to maintain the high market share. When the growth slows down, if they had been able to maintain the highest market share, they become cash cows, or they become dogs if they have a low market share. 

As a particular industry matures and its growth slows, all business units become either cash cows or dogs. The natural cycle for most business units is that they start as question marks, then turn into stars. Eventually the market stops growing thus the business unit becomes a cash cow. At the end of the cycle the cash cow turns into a dog.

The overall goal of this ranking was to help corporate analysts decide which of their business units to fund, and how much; and which units to sell.