Existing systems will only be completely removed and replaced with something new if there is a strong economic case.

The same engagement phases must be worked through for both cases, but they may happen in a different order.

When modifying existing systems, discovery and data collection will be performed early in the process, as part of buiding a conceptual model. This understanding will be used to develop requirements and designs.

When building new systems from scratch, discovery and data collection activites will be conducted at different times for different reasons.

• Discovery can be performed to conduct market research on competitors.
• Discovery and data collection can be performed to identify potential components as part of building up a conceptual model as part of identifying requirements and designs.

Discovery and data collection as part of conceptual modeling can happen at different times for different reasons.