The crosspieces of the ladder are never designed for rest, but for supporting the foot when the other steps for a higher level.

梯子上的横档从来不是用来休息的，只是为了在一只脚迈向更高处时，另一只脚可以有一个支撑。

youdao

Manipulators use the above example of a ladder of supporting bids to absorb sell orders and serve as a cushion against any selling pressure.

FORBES: 'Da Big Kahuna' Wipes Out On Stock Manipulation Ladder