Indications that you need to sub-divide a service into components:

- Quality of service requirements
-   
    - are there large variations in response times
    - ...in transaction processing times
    - The business might treat categories of customer differently
    - We should actually sub-divide our sales service into RegularCustomers component and StrategicCustomers component
- These things can start to show up when the business starts asking you to treat something (like a customer) in little different ways throughout the system.  You end up with a bunch of if statements asking the same question.  
-   
    - Ask the business if this is really a new business component
    - Fork the code base and let them grow apart.  This is liberating as you don't have to maintain both component requirements in one code base.
- More examples
-   
    - Airlines - business vs economy class
    - Shipping - frozen goods vs regular toilet paper
    - Billing - charging credit cards vs invoicing