For an ongoing project/release/sprint, the changes to the model will take lesser time compared to writing new or, even identifying and updating existing manual test cases. This is the core advantage of MBT itselfCreator. However, this is with the assumption that baseline models (ie., models that are equivalent to existing production version of the application) exist.
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The utility also identifies and stores saves the Object Locator information into Creator, thus helping to avoid additional task of manually doing the same on per web page object basis. See section “Scriptless Automation with Creator” for more information on how this utility can positively impact the overall process.