I would split "not converting" into four different problems, because the fix changes a lot: 1. Wrong traffic: people understand the page, but they are not the buyer. 2. Comprehension: they cannot say what it does from the first screen. 3. Believability: they understand the promise, but do not believe the product can deliver it. 4. Next-step risk: they believe it, but the CTA hides what happens next. The fastest test for me is to look only at the headline, subhead, primary visual, and CTA, then ask: "What changes for the user after they click this?" If the answer is unclear, it is a landing-page problem. If the answer is clear but unsupported, it is a proof problem. If the answer is clear and believable but people still hesitate, the CTA probably needs to say the next screen plainly: see sample report, book demo, start trial with card, upload a file, connect an account, etc. Most early SaaS pages hide the riskiest sentence. Writing that sentence plainly is usually where the leak shows up.