Quicken currently requires that the CSV file you wish to import must match the field structure that Quicken expects. This requires hand-editing the CSV file itself in an app like Excel or Access to insert fields, change field names, and/or insert data.
For example, one pain [Edited - Language] is requiring the ACCOUNT destination in the CSV file for each data record. I would venture that 99 out of 100 times, the user will be IMPORTING the CSV data into ONE particular Quicken account since the data will no doubt be downloaded FROM one unique bank or FI account at a time.
Also, it should be pretty easy for Quicken devs to program a field-matching front-end rather than, again, requiring the user to edit the CSV data and fields directly. Here's a fairly common means of field matching that many apps, including MS Outlook, use to handle external data imports. Given that many institutions are eliminating QFX exports in favor of CSV, Quicken should make the process more user-friendly. Some institutions, like Bank of America, have also limited the look-back of Quicken WebConnect downloads to THREE months. So if you are a new user, you may want historical data that's ONLY available via CSV.
[Edited - Readability]