Find the actual friction
Repeated data entry, spreadsheet handoffs and manual report preparation often indicate a missing workflow connection, not necessarily a failed enterprise system.
Define a narrow outcome
A useful small integration has a clear owner, data contract, failure state and support plan. It should reduce a specific burden without creating an undocumented dependency.
Know when small is not enough
Security, reliability, scale and vendor constraints may justify a broader replacement. Requirements work should test those constraints before the organization commits to either path.