Data points are running into thousands, even millions these days. For a normal human being, it gets harder to understand the real meaning behind the data. Also, you need to be a domain expert to understand what the data is about. This creates insights that are understood by a small audience and not used widely throughout the organisation.
By combining data, visualisations and narrative together you will get data storytelling. This is done to minimise the clutter in a visualisation, show only the data that counts and give some textual explanation to that data.
Data storytelling makes it easier to read reports and visualisations for a broader audience that can understand the data. Understanding the data leads to actions and more attractive reports and dashboards.