Those are two different claims and we keep them apart deliberately. “Demand” means Apple reports people actually searching that phrase, and the opening is a real way in. “Competition” means Apple reports no volume for any phrase on your report, so all we can honestly say is which one has the weakest apps sitting in it.
A competition-based pick is not evidence that anybody is looking for your app. It is the least defended door in a building we cannot confirm has visitors.
The usual reason a whole report comes back this way is that the phrases are very specific. Apple only reports volume above a floor, and a genuinely narrow niche often sits under it.