Rewriting bits to 1s or 0s is very slow especially in mechanical drives and is hard on equipment. Even SSDs have a rated max writes, if we rewrite all data every delete it will decrease the lifespan of hardware.
This is why is assumed they mark them to overwrite. Google knows a lot about what makes drives last longer, and OS and drive firmware makers have known for decades too.
Rewriting bits to 1s or 0s is very slow especially in mechanical drives and is hard on equipment. Even SSDs have a rated max writes, if we rewrite all data every delete it will decrease the lifespan of hardware.
This is why is assumed they mark them to overwrite. Google knows a lot about what makes drives last longer, and OS and drive firmware makers have known for decades too.