There are four main stages of the product life cycle: Introduction, Growth, Maturity, and Decline. Some examples of the different types of marketing styles and research necessary for each stage are: First, Introducing a new product into the market is going to require knowing information on your competition, buyer behavior, and distribution channels. Second, Growth-You will need to recognize new or improved competitors, possibly consider expansion in production and markets, and figure out how to maintain a positive image to your consumers. Third, Maturity- When your product becomes you will need to research your competitors more than anything else so you can potentially obtain their customers. Fourth, Decline- If your product reaches the decline phase, you will need to work diligently to get as much profit out of sales as possible. As your product comes to a decline stage, you might also want to consider going back to the drawing board to get creative with new ways to change the product completely to revamp sales. Read more about this aspect at: 

http://blog.marketresearch.com/using-market-research-during-each-product-life-cycle-stage