In the shipped kits, (at least the one I got) the ESCs need no soldering of connectors but have connectors on all leads. So have motors.
ESC outputs, all in Blue color are marked "ABC". Motor leads are color coded.
So some would begin wondering how to hook these up properly. But the general answer is just plug each one to the three motor lead in any order. If it later turns out the motor runs backwards, just swap two of the leads and all is fine. A more proper answer is:
"There are only six ways to connect the ESC to the motor: ABC, BCA, CAB, ACB, CBA, and BAC. The first three ways will make the motor spin one direction, and the other three will make it spin the opposite direction. So, you have a 50-50 chance of randomly connecting the ESC to the motor and having it spin correctly.
If the motor does not spin in the correct direction, then reversing any two wires from the ESC to the motor, such as A-C-B, will reverse the direction. This applies to industrial AC motors as well, and it does not matter which two wires you reverse."