Buying
What a price on this site means.
Prices are exact
USDG has six decimals. Every price crosses between the contract and the screen through one function, so the factor of a thousand has exactly one place it could come from. A collection priced in something else is shown in that token's own units: never divided by a guess.
The floor is fillable
A floor built from listings whose seller has since moved the token is a number nobody can trade at. The floor here resolves the whole book of a collection and counts only what can actually be bought, so it can be higher than the lowest listing you see elsewhere, and it is the one you can hit.
Sweeping
sweep buys the floor in one transaction and skips what has gone stale rather than reverting: it emits a Skipped line for each one and only fails if it filled nothing at all. A sweep that reverts because one of forty tokens moved is a sweep that wastes gas to teach you nothing.