Each cryptocurrency exchange has its own confirmation requirements. Coinbase has recently updates its confirmation requirements for Bitcoin (btc), Litecoin (ltc), Zcash (zec) and Ethereum Classic (etc).
Higher amount of confirmations mean more security but it also meant longer waiter times for deposits.
Coinbase has reduced the number of confirmations to safe level.
Here are the changes made by them.
1) Bitcoin – Current confirmations: 6; Proposed: 3
2) Litecoin – Current: 6; proposed: 12
3) Zcash – Current: 18; proposed: 12
4) Ethereum Classic – Current: 5676; proposed: 3527
Until now, Coinbase was dynamically adjusting the number of confirmations which was something not liked by end users. But, they now how much time it can take for deposits.
If you noticed, proposed confirmations in case of Litecoin have actually increased as that reduces the risk of potential 51 percent attack. Few months back, Ethereum Classic blockchain was 51% attacked and Coinbase increased the number of confirmations to 5676.
In case you are wondering why bitcoin has so less confirmations, it is due to high hashrate that it enjoys. Infact, Bitcoin has the highest hashrate and that is what makes it the gold standard in crytocurrencies.