Here's why:

* Hypothesis: A hypothesis is an educated guess or proposed explanation for a phenomenon. It's a starting point for scientific investigation.

* Testing: The goal of an experiment is to gather evidence to support or refute the hypothesis. By designing an experiment that systematically tests the hypothesis, scientists can determine if the proposed explanation is likely to be true or not.

Think of it this way:

* A hypothesis is like a question you're trying to answer.

* The experiment is the method you use to find the answer.

Example:

* Hypothesis: Plants grow better in sunlight than in shade.

* Experiment: Growing two groups of the same type of plant, one in sunlight and one in shade, and measuring their growth over time.

By comparing the results of the two groups, the scientist can determine if the hypothesis is supported or not.