Why it matters
Visitors decide in seconds whether a page is for them. If the visible screen doesn't say what this is, who it's for, and why care, many never scroll to find out. People do scroll, but only after the top screen earns it.
How it works
Strong above-the-fold treatments answer three questions instantly (what is this, is it for me, what do I do next) via a clear headline, supporting line, and visible call to action. The fold varies by device, which is why the phone version deserves the first check.
What to do about it
Screenshot your homepage's first screen on mobile and show it to someone unfamiliar for five seconds. If they can't say what you do and for whom, rewrite the headline before touching anything else.
