Most organizations run these twice a year, which is a reasonable amount. If you want a more principled way to determine the right frequency, consider how much time you’re willing to invest into addressing the issues that get raised. If you’re already struggling to address concerns from biannual surveys, then it doesn’t make sense to run more frequent surveys. You’ll just annoy folks who take them, who will complain that you’re running another survey before addressing the previously raised concerns.
