Correct or Incorrect? "Iterate on"
Solution 1:
The Cambridge dictionary says to iterate is to repeat a process.
The common usage these days is in a computer program where a repeating loop uses an increasing (or decreasing) value to iterate on, or repeat, until a result is reached. The sentence given above describes this process using the user's insights to repeatedly focus or iterate on the needed content and the overall design.
The Cambridge use shows that the form of the sentence given is correct.