Which trading pair you want to choose. Suppose you want to trade a common coins which is listed in both pair. Then which pair you will choose?
In fact, both pair are my favorite. At one time almost all coins or tokens had BTC pair. Now many tokens do not have BTC pair but USDT pair. The USDT pair is becoming very popular day by day.
If my coin has both pair then I will first see in which pair my coins will have more value. If the value is equal then I will choose USDT pair. Because calculation is easy in USDT pair and transaction fee is low.