Assumption
An assumption is a belief that needs to be true in order for your idea to succeed.
How are assumptions used in product discovery?
Product teams make assumptions across five categories: desirability, viability, feasibility, usability, and ethical. Before teams can test their assumptions, they have to identify them—which isn't always as easy as it sounds. Teams need to be able to see their assumptions before they can test them.
The more specific the assumption, the easier it is to test and the faster teams can evaluate which ideas will work. Teams that adopt an experimental mindset treat their beliefs as suppositions that need to be tested rather than as assumed facts.
By identifying and testing specific assumptions, product teams can quickly determine which ideas might succeed and which to discard—without building complete products.
Learn more:
- Assumption Testing: Everything You Need to Know to Get Started
- Evaluating Solutions: The 5 Types of Assumptions that Underlie Our Ideas
Related terms:
- Assumption Testing
- Hypothesis
- Desirability
- Feasibility
Last Updated: October 25, 2025