If we are talking about scammers who accept payments directly to a card or an electronic wallet, then indeed the money does not lie there for a long time. This happens because control by a bank or an electronic payment system in relation to individuals is much weaker than legal ones. Legal entities that receive questionable payments and immediately withdraw them will very quickly fall under the supervision of the monitoring service, and will probably receive an account freeze until they give a reasonable explanation. Repeated suspicious behavior can lead to blocking of the account, termination of the contract and getting the organization blacklisted. Recently, some European banks have begun to withhold up to 10% of payments on a special account, which will be unfrozen only after 12 months, if the bank begins to doubt the cleanliness of the serviced company. Since the buyer (individual) and the outlet (legal entity) are involved in the chargeback procedure, the buyer has a higher chance of finding his money on the seller's accounts.
Also, according to our practice, scammers always had funds in their account. Fraud is most often aimed at a group of people who make payments at different times, so the funds constantly turn around in the account with fresh receipts and are not withdrawn so quickly for the reasons described above. When refunding funds, we have not yet encountered such a situation that there was no money on the scammer's account.