Eveybody does it different.
The cables, throttle linkage, hood release, hood hinges, door hinges, and door latches, (Yeah, I know they aren't in the engine compartment), I lube with a silicone spray. WD40 doesn't seem to last, and white lithium grease, (which is often recommended), seems to attract dirt. A small squirt on whatever I think needs lube while protecting the rest of the area with a rag seems to work for me.
It may not be necessary, but my cars are usually around for a while and the lube does seem to disappear. That's with no washing as such, just wiping things down regularly. If you were to pressure wash, I would think quite few areas would lose some of their lubricant.
:dunno
Charles