Required Fields in SPD Workflow

There is a strange and surprising thing happening with SPD workflows. Suppose a workflow gets triggered on a new item creation or an item modification. Consider the scenario where this workflow creates a new item in another list which has only Title as the mandatory field. After developing your workflow, you go to the target list (where you have to create a new item through workflow when a new item is created or when an existing item is modified) and changed a few fields as Required, surprisingly, the workflow does work without any issues. Only thing is that when a new item is created, the newly changed mandatory fields are not filled by the workflow. But there is a caveat. Once you have to make some changes to the workflow and compile it again, then it won't allow you to do so until all the required fields have been filled.