The zero confirmation discussion has been talked about for quite some time in the cryptocurrency space and well before bitcoin cash existed. In the early days, there were many heated debates on whether or not accepting bitcoin transactions without a miner confirmation was safe. Zero confirmation transactions are broadcasted throughout the network’s nodes but have not been etched into the blockchain. A confirmation or blockchain record doesn’t happen until the miner mines a block which contains the specific transaction. The instant transaction topic is controversial because some believe the idea opens merchants up to double spend attacks. A double spend consists of spending the same transacted bitcoin twice before the miner confirms the transaction’s first confirmation.
On the Bitcoin Core (BTC) blockchain the average time is traditionally ten minutes, but when blocks are full that time can be extended to days. Even the bitcoin cash chain has a wait time of ten minutes and blocks are never full. For this reason, lots of BCH supporters believe bitcoin cash is a perfect network to start the widespread use of zero-confirmation transactions.