When conducting scientific inquiry, there has to be a rationale behind the investigation. You, as the researcher, have to ask essential questions in order to know exactly what it is that you want to explore, so that you can locate the resources that you will use to conduct the investigation.
After applying a research methodology, you should come out with plenty of information that comes as a result of your inquiry. This information is the data. What happens next, is that you take that data and organize it. This can be done categorically, or in order to establish a correlation. What came up as a result of the questions that you asked and organized your study?
Hence, the reasoning for collecting data and interpreting the results is precisely to give your investigation the purpose that it deserves. There has to be, as stated before, a rationale, or a purpose, that drives the investigation and moves it forward. Without this rationale there is no point in investing time and methods into the scientific process. Hence, the data and its results provide that purpose that would make the investigation valid, and worthy.