Times that people play with form in music is when there is a sudden key change in the middle of a song right after a chorus or a bridge normally. In the song All I Want by Olivia Rodrigo, after the second pre-chorus, there is a key change which takes the key of the song up an octave to, most likely, make the song more interesting or compelling. I would say the attempt was very successful. Doing this added depth to the song and it provides the singer with more opportunity to express emotion through a louder and more heart-tugging melody. When this happens, it shocks the listener because they didn't expect a change in the song, but even though the audience didn't anticipate it, it's creative, strategic, and respectful to both keys.
This is such a great example. I will notice a change in form in a song almost every time.