Statistical modeling is a mathematical representation of reality, essentially an equation which can generate results reflecting what goes on in real life.
Your data is based on what you have observed or recorded, under the conditions that were present at the time. But what if you wanted to see how those results would change under different conditions? What if demand suddenly rose? What if there were less staff? What if you raised prices? How would these changes to the environment affect your outcomes?
Statistical models describe the relationships between the variables in your data. Using these relationships, the model then attempts to simulate the process which generated the data; it attempts to simulate reality