We always mine LTC if there are no other coins more profitable at the moment. This is just variance. With our current hashrate we are expected to mine one LTC block per hour, if we would put all our hashrate into LTC (which of course we don't do, because we mine also other coins, but let's assume this for simplicity). So it's 12 blocks within these 12 hours mentioned. But this is a long-term expected average. Mining is a random game and you can mine five blocks in an hour and then don't mine a block for five hours. Every pool has such variance and it's completely normal. We have periods with 35% profitability and then periods with 250% profitability. You shouldn't neigher worry nor get excited with short-term stats.