My studies of the online RNG explain that the shuffling of the cards uses a variety of inputs, including player mouse movements and barometric pressure, among other seeds. These seeds produce the randomness of the shuffle. Once the deck is shuffled, it remains static till the end of the hand. At no time is the order of cards changed during the hand. That would be akin to a dealer in a card room shuffling the cards after the deal, the flop, and the turn. While the results would still be random, it just never happens in a NORMAL hand. (There are a few instances when part of the deck can be reshuffled, due to dealer error, but they are very, very rare.