Use cases
Paste notes, pick a count, copy the question and answer text.
Class notes
Need: A first set of questions from a paragraph.
What you get: Q/A text you copy. No review calendar.
A short chapter
Need: Five, ten, or fifteen cards.
What you get: That many pairs, still as text.
Not a study account
Need: A synced deck and a review schedule.
What you get: Nothing synced. Copy the text into a tool you already use.