Why was this Weather Provider API developed? Because obtaining necessary meteorological information is key to controlling the effects the weather can have on our operations. That is why it is very important to have this meteorological information more easily accessible.
Unfortunately, accessibility is by nature quite a problem: there is a lot of information available, and not all of it in the same output format. Even a single institution can often have multiple output formats, with different names, for the same content. Some are directly accessible from a URL, while others require a complete API with authorisation rules. Some use a standardised GRIB file format, while others use their own NetCDF format. Other information could even be a CSV file or a table on a webpage.
And once you get all this information together, you will probably still have to format and parse everything to arrive at something you can use. That is a lot of time and effort that you need to put in before you can even get started.
The purpose of the Weather Provider API is to provide a single, fixed form of access to a large number of data sets, output in a standardised format in the file format and system of units you need.
This means less time and less effort to get the information you need and more time to get to the results you want. And if we benefit from this, why not other people too?