The easiest way to simply explain it is kinda like a water pipe. The pressure or voltage is looked at as a constant, the resistance in the circuit is found in the battery, battery cables, and starter motor. By increasing the size of the cables you make the water pipe larger and it flows more current / electrons / water because you have lowered the resistance. If I had ever had an issue I would think about it, but my bike fires super fast and easy everytime. 29 degrees the other day and had not been cranked for several days.
One of the characteristics of the lithium battery from memory is that the more load you put on it the better it works.