Stuff is organized in a manner someone unfamiliar with data handling or programming can understand it.
It takes a little bit to master, an some stuff (like looks and variable passing) is still unintuitive.
It uses a visual data flow approach to transform data step by step from one form to another. This approach is much better for data transformation. It is also less error prone as operations take place on columns or rows of data, not cells. But you wouldn't try to create a set of company accounts with it.
Most nodes (there are official and 3rd party nodes) do have error output, and there's a console to inspect what's going on.
You can also inspect data visually in most nodes.
Even someone who is not used to play with data, who doesn't understand consistency and yada yada will understand the advantages.