In formulating a hypothesis, you will be making a declarative statement (a proposition) that has an actual truth value. That is, it is either true or it is not true in real life. However, since we will assess that truth using a test sample then measuring that truth value will never be 100% certain in the same manner that confidence intervals can never include 100% of the possible choices for a particular statistic. Hence, it is possible for you to make an incorrect conclusion.