Block time is the target timeframe between blocks being found/written to the blockchain.  Two minutes is not that bad.  However, if a transaction requires 10 confirmations(blocks) to be confirmed, the total of twenty minutes is a long time compared to instantaneous credit card authorizations.  In the case of most cryptocurrencies it really isn't a problem if you look at them as a store of value instead of a quick medium of exchange.  Just my two cents.