Bitcoin block creation is much slower than it needs to be. Satoshi guessed that it might take a minute or so to get blocks across the network, meaning that with a 10 minute block time about 10% of blocks would be orphaned, which she probably picked because it sounded reasonable. In practice propagation is normally done in a few seconds. Other coins like LiteCoin that are otherwise near-copies of Bitcoin tweaked that parameter to be lower and they still work fine.
The key trade-off is that faster blocks cause higher orphan rates, and high orphan rates are thought to promote miner centralization. Ethereum uses a system called GHOST to reward miners whose blocks get orphaned which reduces this effect, allowing faster blocks than would be safe otherwise. But it's not a 30x effect: The main difference is that the Ethereum designers had data from actual usage of Bitcoin and other coins, so they were able to choose less conservative settings than Satoshi had.