If a user imports a file where every document errors, then the progress appears to be "stuck" on "0 documents written." Although the progress bar does change. It would be handy to know that there are errors without having to wait for the import to finish.

The easiest way to get into this situation or test this is to export a collection to JSON, then import it to a new collection. Then import it to the same collection a second time. All those object ids should error because of unique constraints. ie. literally every document in the file can easily produce an error. Imagine this is a very big file.