I would say that the ESCs and Motors are well assembled.
Please do the next, arm the drone (without propellers) and check if the motors are spinning in this direction:
If not, change the polarity, switching ESC-Motors connection. Change
+ -> - and
- -> + and check again the spinning direction of motors.
The 1 and 2 motors are the balck ones and 3 & 4 gray ones.