Chris is writing out why this is in the documentation. We try to release as infrequently as possible so that we don't bring the site down now that we're in testing, but when we do release an explanation will be in the help page.
The answer to your question is that this is a pay per share pool (PPS), which means that users earn a set amount of money regardless of how well the pool does. Our earnings will, over the long term, be equal to the pool fee. But on one day, we could make three times the fee, and then the next day, we could lose money. This is different from most pools, which are pay per last N share (PPLNS) - those pools pay out miners what they actually earn, which means that miners take a hit if the pool is unlucky and gain if the pool is lucky. In the end, PPLNS pools have the same earnings for miners as PPS pools do, but miners cannot count on a PPLNS pool to pay out consistently because payouts are due to luck.
In summary:
- PPS pools (our pool) provide steady payouts to miners and fluctuating payouts to the pool
- PPLNS pools provide fluctuating payouts to miners and steady payouts to the pool
If everything else (uptime, coin selection, etc) is equal, a PPS pool is better for miners. However, if the pool paid out every day, it will go bankrupt the first day it is unlucky, because miners are paid the usual rate and the pool doesn't make enough money to cover all the payouts. To avoid this problem, payouts are delayed by 24-48 hours. The pool is far less likely to go bankrupt because the probability of the pool having three unbelievably bad days in a row is less than 1 in 10000, according to our calculations. If payouts from two days ago exceed today's earnings, that's no problem, because chances are that tomorrow's earnings will not be as unlucky.
Miners still get paid the full amount, it's just delayed by 1 to 2 days. If you were to stop mining, your money would be paid as normal a few days later. This is what allows a pay-per-share pool to remain in operation if there is a string of bad luck.
