Depends how you define “technical requirement” but I’d say 404 for example is an indication of a failure to serve a given resource. If you don’t have logging you won’t know unless someone complains which means you’ll only catch the most visible issues. Same goes for performance - everywhere I’ve ever worked serving a resource was tightly coupled to “how fast can the user retrieve that resource”.
If you buy something at the supermarket, the supermarket keeps a record of the transaction - it's part of the process.
However if you try and link that to entities and build a pattern behaviour across multiple websites then I think you stray into spying.
Also if the tin of beans I bought at the supermarket records audio at home and uploads to the cloud - that's spying.