Most "factories" on the big marketplaces never touched a machine. They are trading companies, middlemen who mark up a real factory and forward your emails. Here is the 60-second test.
Why it matters to your margin
A middleman adds a layer for doing very little. Factory makes it for a dollar, the trader adds thirty cents, you pay the thirty cents forever. On a real order that markup is the difference between a healthy margin and a thin one.
The 60-second test
Ask for the business license and read the scope
Every registered supplier has one. If the business scope says trading, wholesale, or import and export, and does not mention manufacturing or production, it is not a factory.
Ask for a live video walkthrough of the floor
Not a polished file they email you. A real factory can walk the line on a live call in about five minutes. A trader stalls, says the engineer is busy, or sends a recorded clip.
Ask which machines run your product and how many lines
A real factory answers instantly and specifically. A trader goes quiet, because they do not know.
The tell, in one line
Stalling equals trader. Instant, specific answers equal factory. Run this before you wire a deposit, not after.
