The "Boston Matrix", interesting read on wikipedia - puts a lot of whats happened into perspective. An interesting part of the wikipedia article is the criticism;
While theoretically useful, and widely used, several academic studies have called into question whether using the growth–share matrix actually helps businesses succeed, and the model has since been removed from some major marketing textbooks.[6][7] One study (Slater and Zwirlein, 1992) which looked at 129 firms found that those who follow portfolio planning models like the BCG matrix had lower shareholder returns.
The matrix ranks only market share and industry growth rate, and only implies actual profitability, the purpose of any business. (It is certainly possible that a particular dog can be profitable without cash infusions required, and therefore should be retained and not sold.) The matrix also overlooks other elements of industry. With this or any other such analytical tool, ranking business units has a subjective element involving guesswork about the future, particularly with respect to growth rates. Unless the rankings are approached with rigor and scepticism, optimistic evaluations can lead to a dot com mentality in which even the most dubious businesses are classified as "question marks" with good prospects; enthusiastic managers may claim that cash must be thrown at these businesses immediately in order to turn them into stars, before growth rates slow and it's too late. Poor definition of a business's market will lead to some dogs being misclassified as cash cows.
Jetstar <insert franchise here>