This will be a big step towards detaching the altcoin market from bitcoin price fluctuations. We've all seen what a drastic effect that has had in the past few days.
Until now, most people are forced to buy a very limited range of coins on Coinbase before sending them to a true exchange with a large amount of altcoins. In a recent interview, Bittrex CEO Bill Shihara outlined the company's plans to begin accepting fiat deposits from most customers in the near future. Hopefully this will simplify the altcoin purchasing process for newcomers and increase mainstream adoption.
https://cryptosumer.com/2018/02/02/bittrex-accept-usd-fiat-deposits-according-ceo-bill-shihara/