Looming a point will light up a bulk, which is the living picture of so called "congregate effect".

做活一个点，照亮一大片，牵一发而动全身。这就是“点式效应”的生动写照。

youdao

Although there are a relatively small number of pedicabs operating in a small part of central London, they have a disproportionate effect on traffic congestion and congregate in pedestrian areas, TfL claims.

BBC: Pedicabs law change call by London mayor Boris Johnson