There is a myth that information overwritten multiple times can be recovered. The current technical reality is simple: If data has been overwritten magnetically (on HDD) or electrically (on SSD), it is unrecoverable.
What sometimes happens is that the file was not completely overwritten, or a previous version is recovered that was in another physical location on the disk (thanks to defragmentation or temporary copies).
On SSDs, the TRIM command makes recovering deleted files very difficult, as it physically clears cells within minutes. On HDDs, if no new data has been saved on top, recovery is nearly 100%.
