It is tempting to try to find out everything about an ancestor all at once. (Especially if there is nothing known.) But, when we start with little focus, it makes our research more difficult. It is harder to track what records have been searched and what the results are.
If we start with a specific question we can determine what types of records might best answer it. If we want to know when someone was born we would look for different records than if our question is where was someone married.
Next, we examine the documents with our research question in our mind. We ask ourselves:
Is there an answer to the question?
Is it a complete answer?
Is it a partial answer?
Is there another document that also answers the question?
We repeat this process for all the documents we identify.