One easy rule of thumb is if you're looking to lubricate something WD40 is never the correct choice. It's not a lubricant, it's for cleaning/breaking shit loose.

Wd40 is good for preventing rust, and helping to get things that are seized moving again. If you want to lubricate a door hinge, something like 3 in 1 oil is a good choice.

Not OP, but not really. The real issue is that WD-40 is kinda like duck tape. It definitely has its uses, and hoo boy are there a lot, but it's too much power too fast, and corrupts young engineers and repair people into using it as a "fix all tool."

Sewing machine oil is a wonderful penatrating oil. This is what you use on tools inside the house that mostly just get a bit dusty.

WD-40 does contain some oils and can be used as a penatrating oil, but it's mainly a cleanser. You shouldn't leave it on anything that will be damaged by cleansing solutions, so motherboards, plastic in general.

For a general use oil, for hinges and things, I will clean with WD-40, and then once I have cleaned it I wipe it down with 3 in 1 penetrating oil, for things like door hinges, or sewing machine oil for more delicate tools.

Edit: I had not seen the flowchart below when I wrote this comment, but it illustrates my first point beautifully

Mechanical stuff you're looking at grease, oil, penetrating, or dry. I found this with a quick search for more info. Personally I've found white lithium grease to be the best general purpose one for my needs (squeaky hinges, drawer wheels) but it can be pretty messy if used in the wrong spots. For most fast moving things with fine parts (like a bike chain) I really like wax lubes but they can get gummy sometimes so silicone works well too.

For sex I prefer water based because it is easier on toys and doesn't make me fear for my life when trying to wash off in the shower after. It isn't usually as long lasting as silicone based but it can be 'revived' with some water or other fluids. Anal I prefer oil based (shout out to Boy Butter because the name and logo are ridiculous but it works amazingly) but it also damages condoms so like if you're not using an insertable go for the protection and silicone combo. For oral I'll concede that wd40 actually has a use case here.

If you're looking for an actual "all-purpose" lubricant try tri-flow lubricant. It's technically a chain lube but it works pretty well for most light duty household stuff and it sticks around a whole lot longer than WD40. Generally wherever you think WD40 is a good idea that stuff will usually work better. The only downside is that it smells strongly like bananas for a while after you spray it on because it contains banana oil. It's not a bad smell but it's definitely noticable.

WD40 is a bit of a catch all. It kind of does a lot of things but it isn't great at any of them. It's kind of a penetrating oil for busting things loose but it doesn't work nearly as well as an actual penetrating oil. It's kind of a part cleaner but it won't work nearly as well as an actual part cleaner. It's kind of a lubricant but it won't work nearly as well as an actual lubricant. If you had one can of stuff to bring with you to a deserted island then WD40 would be the best thing to bring. But other than that there is always a better dedicated spray for whatever you want to do.

Simple. WD40 for most things, WD40 silicone for vinyl windows. Grease for bike chains.