At Nailted we have a set of approximately 120 questions divided into 10 metrics.
In each survey, we include 10 questions, one corresponding to each of the metrics (11 questions if the person has not answered the eNPS question that calendar month).
So, if the company has a recurring survey sending setup every two weeks, it would take a person approximately 6 months to complete the entire cycle. If the company had a three-week sending configuration it would take a little over 9 months to complete.