Looks like you're zeroing the disk. Hard drives are faster on the outside of the platters compared to the inside because there's more rotational velocity on the outside. Since the data is moving directly across the disk as its writing, yes, you'll see a speed difference during this process.

See https://superuser.com/questions/643013/are-partitions-to-the-inner-outer-edge-significantly-faster

Also related :)

Formatting is almost instantaneous, this seems to be overwriting the files for a safe deletion (a.k.a. deleting white space). In any case, it's weird to measure a safe deletion speed as MB/s, as the operation involves multiple overwrites. I'd just format it using gparted if you don't care about deleting the white space.

That is very slow, unless the drive is connected over USB or failing or something, a drive of that capacity should easily be able to handle sequential writes much faster than that. How is the drive connected, and is it SMR?

And whatever you do, stop shouting! 😁

https://youtu.be/tDacjrSCeq4?si=BLnrZ3nLaf5UiMhy

initializing the filesystem at the same time as zeroing the drive is probably freaking the smr out and causing it to constantly rewrite tracks.

i would have separated the two operations. a sector-by-sector wipe via software which would run at the full sequential write speed the drive internals and interface supports (connecting internally would be faster), then partition and format the filesystem. being smr shouldn't matter here when you're writing sequentially, start-to-end.

alternatively for the wipe, use secure_erase (some usb don't support it though), handled internally by the drive so it runs as fast as it can. still takes awhile with hdd, but can be faster than doing it via software and being limited by the interface speed.

For the fastest you can get, let your drive zero itself https://archive.kernel.org/oldwiki/ata.wiki.kernel.org/index.php/ATA_Secure_Erase.html

Still may not be fast