This is because, as thinking, rational beings, the only thing we have to work with is what we can access via evidence. Evidence is the building block of logic, and thus, reason. Something is accurate when there is enough evidence to support it. Water is wet. This is an accurate statement.
Water is dry.
This is an inaccuracy. More complex ideas require a correspondingly broader range of evidence, but it is ultimately possible to determine the accuracy of a given idea. So, evidence forms a cornerstone of human reason. That which has credible evidence behind it can be considered accurate. That which is accurate can also be said to be true.