The math of shuffling cards almost brought down an online poker empire

> Today many online poker sites use the Fisher–Yates algorithm, also called the Knuth shuffle (which sounds delightfully like a dance). It’s easy to implement and delivers satisfactory results.

Assuming CSPRNG and fisher yates, why is it only "satisfactory"...? What's better...?

Satsifactory in this context is good, not bad.

We live in a euphemistic world where "satisfactory" is presented to failures to not hurt their feelings, but the word also and originally means it's good enough, i.e. delivers an unbiased shuffle.

But it's not just good enough, it's optimal. It is equivalent to picking a random deck from the set of all possible decks assuming your random source is good. More random than a real shuffle.