How far back does recuva go?

I am new with Recuva. Using it on a file server as an additional way to recover deleted files/folders. But it seems like every time I run a scan, it just picks up recent stuff. Like If I delete 25 files today, and look tomorrow, I don't see it? It is weird. How does it work? Why would I see some stuff on a friday, and not that same stuff, but different stuff the next day, or the day after?

Recuva - in a normal scan - just reads what's in the Master File Table. Each file has a record in the MFT and when a file is deleted that record can be reused for another new file. So what you are seeing is the continual allocation, deletion and reallocation of files on your system.

Recuva - in a normal scan - just reads what's in the Master File Table. Each file has a record in the MFT and when a file is deleted that record can be reused for another new file. So what you are seeing is the continual allocation, deletion and reallocation of files on your system.

I have no idea what that means. What I am seeing is. I delete a doc called "work". I scann and I see it. I close and come back a few hours later, it doesn't show up. Do you only have a specified amount of time to recover a file? I am not seeing what I deleted earlier, or Friday

how many people access the file server?

how many file operations happen on that drive per day?

are you running a Normal scan or a Deep scan?

Normal only looks in the $MFT, Deep goes through all the clusters on the drive.

once a file's slot in the $MFT gets reallocated to a new file, the original file has no history to find.