Low odds means if you bet 10 BTC to win 2 BTC at directbet if you bet the same 10 BTC at Nitrogen or Sportsbet you would win 3 BTC. Winning gamblers would never bet at directbet because of low odds.
First, there's not much difference between DirectBet and NitrogenSports.
Second, which one do you prefer? You won the bet and got your money after the game finished. (Directbet) You won the bet but wait for them to accept your withdraw request? (Nitrogen, Cloudbet etc.)