[nick__m]

In high end enterprise storage, the drive do a form of caching (SLC to TLC in background by the drive) and it also does compression and encryption. Look at the Flashcore FCM4 used in IBM Flashsystem. https://www.redbooks.ibm.com/redpapers/pdfs/redp5725.pdf (no affiliation except that work recently aquire an IBM SAN and I am satisfied by this storage unit, it's not like a Purestorage SAN but it's fast enough)

[wtallis]

IBM's drives are exactly why I said "usually don't" rather than "never". SLC caching is still not normal for enterprise drives, whereas it is now universal for consumer SSDs.