TL;DR
Product ideas focus on solutions.
Assumptions get behind the ideas to common beliefs.
Testing assumptions is usually faster and cheaper.
Assumption testing helps to validate many ideas at once.

When you make this shift for the first time, you’ll be surprised how quickly you can move through your ideas to sort out the ones that are most likely to succeed.

Have you tried testing assumptions in your projects? How did it go?

This works because your ideas often share the same core assumptions about the problem, customer, the value, etc.

Suppose you have several ideas for how to solve a problem. If you test one idea and it fails, you probably didn’t learn much about your other ideas. But when you test an assumption, you are likely to learn information that helps you make decisions about all your ideas.

Testing assumptions has another major benefit over testing product ideas: you get more bang for your buck… a lot more.

Testing some assumptions will still require you to build something, but what you build will often be smaller and less expensive than what you’d need for testing the full idea.

To test an idea, you often have to build something and try it out. For most ideas, this is not a quick or inexpensive process. By contrast, when you identify the assumptions behind your idea, you’ll find you can test most of those assumptions with a handful of conversations.

Product ideas are focused on providing solutions that deliver value to some customer. Assumptions are the things you believe about the problem, the customer, the feasibility of your idea, the value, etc.