Floyd Mayweather's insanely expensive Bugatti didn't sell at auction this weekend ... despite a $1.9 MILLION bid ... because the number was still much lower than Floyd was hoping to get.
As we previously reported, Floyd put his white 2011 Veyron Grand Sport on the auction block at the Barrett-Jackson auto show in Scottsdale, AZ this weekend.
The boxer was expecting to make a profit after reportedly paying $3.5 mil for the whip ... but that's not how things went down.
We're told the reserve on the car (the lowest number he would agree to sell the car for) was $2 million .