Why does the word order change when I use a definite object?

I’m getting a handle on the basic subject-verb-object structure, but whenever I use the definite conjugation (like 'olvasom a könyvet'), my Hungarian tutor keeps telling me the word order feels unnatural if I don't move the emphasis correctly. Is there a strict rule for where to place the focused element before the verb, or is it purely intuitive based on what I’m emphasizing? I'm trying to internalize the syntax so I can speak without stuttering over these shifts.