What do we mean by "human effort" and "make data usable"?

I agree with @herrmann. Data literacy is a must. APIs in my view are the best case of accessibility as they imply that cleanup is not needed. Spreadsheets are often more ambiguous when it comes to the meaning of the presented data.

One more aspect that I’m not clear about is metadata and other documentation. A lot of the data on the opendata portal of the Bulgarian government is in CSV format, so it’s available for download and though an API. The documentation however is mostly in Bulgaria for now. Most of the 1600 datasets are easy to use, but should they be penalized as the documentation is not in English, French or German? Should the UK data be penalized since it’s documentation is not translated in Bulgarian, Italian or Spanish?