Take an example of extraction logic where you are asking respondents to select brands in the source question and asking for multiple follow up questions for the selected choices.
Now if you wish to make changes to the source question like either add or remove brands, then you have to set up extraction again for all the follow up questions. This is a tedious process.Instead, you can use Locked Extraction when setting up extraction and any edits or changes to the source question will be reflected automatically on the follow up questions.
To set up extraction:
Once you have set up locked extraction, any change you make to the source question will automatically be reflected on the extracted questions as well. You can add/remove/edit answer options in the source questions and changes will also reflect on the extracted questions.