This tutorial provides a simple and effective way to clear up significant storage space on a mobile phone by targeting hidden duplicate files within WhatsApp. The creator explains that whenever you send a photo or video to someone, WhatsApp creates an extra copy of that file in a specific “Sent” folder, which consumes double the storage without the user realizing it. By navigating through the File Manager to the WhatsApp Media folder and specifically deleting the contents of the “Sent” folders for videos, images, and audio, users can reclaim several gigabytes of space without losing the original files they received or saved. The video emphasizes that this action is safe and highly beneficial for anyone struggling with a “storage full” notification, as it only removes unnecessary outbound copies.