Companies are required to improve their customer experience, stay competitive, be agile, and increase their revenue per customer by having better response times and less processes.

To be able to accomplish this companies need to structure their business in 3 stages

• in a pre-sales stage you will need to do marketing, contact your lead, create opportunities, and try to finalize a sale
• in the sales stage, after you guaranty the sale you need to send orders/quotes/invoices and track payments
• after the sale (post-sales), you need to be able to provide support to the product you sold and create opportunities to do more cross/vertical sales

These 3 stages are valid for every product/market and type of sale (offline/online), .....

Read more at  http://www.businessandmanagement.org/launch/242/v.aspx