Personally i will prefer binance than kucoin why because binance has high trading volume and their android app is awesome
And don't forget their 50% discount in every transaction if you use their token to purchase. Well everybody loves discount and this is a good strategy to attract more traders. So isn't it obvious why everybody love binance?
In other way, I also use kucoin but just in some rare moments like when my coin isn't listed in binance.
Kucoin offers the same discounts if you have Kucoin shares. I still prefer exchanges like Cobinhood with no fees but they are not popular yet and low volume. I overall prefer Kucoin over Binance as they have many interesting low cap coins, but the real strong projects get listed on Binance as they have much harder requirements to get listed as having at least some prototype in development.