[1] Legislative bodies sometimes have special rules regarding this type of amendment.
For example, the Continental Congress had a rule stating: "No new motion or proposition shall be admitted under color of amendment as a substitute for a question or proposition under debate until it is postponed or disagreed to.
This has the effect of skipping steps of the legislative process, such as the need for a bill to be passed by a Congressional committee.
This is possible because there is no general requirement that amendments offered by senators on the floor must be germane or relevant to the bill being considered.
[5] It could be used to improve a poorly worded motion or resolution which helps to pass it.