Determination should include

selecting a product or service
modifying an existing product or service
developing a new product or service, including constructing a prototype if necessary.

Criteria for selection should include

factors of production (e.g., natural resources, human resources, capital resources)
cost of product or service (e.g., to business, to customer)
availability of production factors
product or service requirements (e.g., for delivery to business, for modification/manufacture)
human resources requirements (e.g., to sell/deliver product service)
space requirements (e.g., for display, for inventory storage)
determination of whether product or service matches established or anticipated customer need
equipment and technology needs (e.g., for demonstration, promotion, display).

What is the difference between products and services?
What is a product mix?
Why is product or service planning important to a business?
How does a business select the product or service mix to be offered?
What is seasonality? What effect can it have on the sale of a product or service?