Customers adopt the product without migrating off their existing system. It works on top of, beside or inside the host, record or workflow they already run.
How Drop-In Adoption works
Replacing a system of record is expensive and risky, so buyers delay it. A product that attaches to the existing system avoids that decision and can be adopted by one team at a time. Some companies later become the system they first attached to.
How companies won with Drop-In Adoption
From the win chains in Strategy Canon case studies: what the winner did, and what its rival did at the same step.
VizQL: drag-and-drop visual queries over data customers already have
What it did
VizQL, from the founders' Stanford Polaris research, turned drag-and-drop gestures into queries run live against the customer's own databases, no SQL needed (Desktop, Dec 2003)
Qlik
Qlik's innovation was an in-memory associative engine: developers wrote load scripts to pull data into it and built the apps
What existing system did the customer keep, how did the product attach to it, and did the company later become that system?
Who names it
Author
What they call it / where it appears
Strategy Canon +
Editorial concept; the vernacular contrast is "rip and replace"
Note. Adoption that required replacing the existing system is absent. Record whether the company later became the customer's system of record. A compatible replacement (a "drop-in replacement") is a different idea: it replaces the old system.