Formitor's standard check submits to your form's server endpoint — that proves the back end accepts a lead. But a form can pass that check and still be impossible for a real visitor to submit. To catch this, Formitor also opens each form in a real browser (the render-check) and flags two problems:
“May not be submittable” (at-risk): the form has a required field that is hidden — usually a conditional field that was left marked required after being hidden, or a required checkbox/upload that never shows. A visitor fills in everything they can see, clicks Send, and nothing happens (no error). Fix: in your form builder, either un-require the hidden field or fix the conditional logic so the required field is visible when it applies.
“May be unreachable” (unreachable): the browser couldn't find a usable form on the page at all — e.g. an Elementor popup whose trigger is missing, a form removed from the page, or a builder template that no longer renders. Visitors can't open the form to begin with. Fix: open the page yourself and confirm the form actually appears (and the popup opens).
These are advisories — your server check can still pass them. Each flagged form is named in the dashboard (and badged in the form list) so you know exactly which one to open. The render-check runs on a slower (weekly) cadence and never submits anything.