On an SSD, data deletion works a little differently than on an HDD. When you delete a file on an SSD, the operating system simply marks its space as available for overwriting, but the data itself is not physically destroyed right away. This is due to the features of the SSD, where data is distributed across memory cells and technologies are used, such as depreciation and garbage collection. That is, on an SSD, deleted data can remain on the device until it is overwritten with new data.
Now, as for the SSD Secure Erase [/spoiler], this is a special command that activates the process of complete and secure deletion of data. This process erases all data on the SSD, including internal residual data that was not deleted in the usual way. Secure Erase overwrites all SSD memory cells in a special way, making data recovery impossible.
Thus, Secure Erase is needed in order to completely clear the SSD of data, ensuring complete destruction of information, which is important if the device needs to be sold or disposed of, and you need to eliminate the possibility of data recovery.