Benefits of scale is illustrated simply by the phrase "you have to have money to make money." Multiple mechanics are at play for benefits of scale, and they are often multiplicative.
For example, with large enough scale, you may no longer have to spend as much of your resources on recruiting talent, advertising your brand, or establishing a production pipeline.
Scale is also important particularly for litigation; because a single lawyer or small team of lawyers can represent a huge corporation in a given legal case, the resources needed to fight individual suits are often miniscule in comparison to the resources brought by the prosecution.
The mental picture of the benfits of scale is an exponential graph, where opportunity is exponentially correlated with capital scale.