Demand that already exists
Capturing demand means meeting people who are already looking. Someone whose pipe burst is searching right now, and the job is simply to be findable and credible at that moment.
This work is satisfying because it converts fast and measures cleanly. It's also capped. You can't capture more demand than currently exists, and your competitors are standing in the exact same doorway.
Demand that has to be made
Creating demand is the harder, slower discipline of making someone want something they weren't yet looking for. The homeowner who wasn't thinking about remodeling until something made the idea feel possible.
This work converts slowly and measures poorly, which is exactly why most businesses avoid it and crowd into capture instead.
The trap
A business that only captures demand is permanently limited to the size of the existing market and fights for it on price. A business that also creates demand expands the market it gets to capture later, and arrives in that future doorway already familiar.
The mistake is using capture tactics to try to create demand, or expecting creation work to convert like capture. They're different jobs. Funding only the one that measures cleanly is how a business stays exactly the size of today's demand forever.