Speaker was dead. It started making a crackling sound and progessively got worse until it was no longer functional. The phone had never been dropped and no liquid spills.
The repair went smoother then I anticipated. No hidden surprises due to the well written guide.
I rarely made any contact with the metals of the phone. I made sure to use the tweezers as much as possible. As a result I did not have to clean the metals as suggested in the guide.
Ensure you are using the correct tools. iFixit provided all of the necessary tools for cheap.
Lastly, do not tighten the srews too tight. They are very delicate screws.