Direct answer

A project assumption is something the implementation plan treats as true before it has been fully proven. Examples include data being available on time, key users being available for workshops, a standard integration being sufficient, or a country process fitting the global template. If an assumption turns out to be false, scope, effort, timeline or solution design may need to change.

Why assumptions matter early

SAP Activate places planning, scope, governance, resources and workstream preparation in the early phases of implementation. That planning depends on explicit expectations. A hidden expectation behaves like an unmanaged risk; a documented assumption can be validated, assigned to an owner and converted into an action when evidence changes.

ASSUMPTIONS TO VALIDATEKey users available for Explore workshopsLegacy data ready by migration cycleStandard process covers local requirementThe team turns assumptions into validation actions before they become delivery surprises.
A practical assumptions review links each assumption to an owner, evidence and a date by which it should be validated.

Four ways an assumption changes delivery

First, it can change scope: a process believed to be standard may need an extension. Second, it can change effort: data cleansing or integration work may be larger than expected. Third, it can change sequence: a dependency that is late can block configuration or testing. Fourth, it can change risk: an uncertain assumption may need mitigation before the project commits to a milestone.

ASSUMPTION IMPACT MAPASSUMPTIONvalidated or disprovedScopeEffortScheduleRisk
An assumption is valuable only when the project understands which downstream decisions depend on it.

How consultants should manage assumptions

Record the statement clearly, identify why it was made, assign an owner, define what evidence will validate it, and set a review point. Link important assumptions to the relevant scope item, estimate, dependency or risk. This complements project estimating and scope definition.

Common mistake

Do not use assumptions to disguise unresolved decisions. “Business will confirm later” is not a useful assumption unless the project records what decision is needed, by when, and what happens if it is delayed.

Official SAP References

Turn assumptions into managed project knowledge.