Right. So go back to the example that I showed. Was my mistake delibarate? If yes, why? If not, why not? How can you, as an outsider tell?
No, I reckon that any mod who saw that being quoted, would look at the context and deem it to be a simple mistake.
I mean, it's generally pretty easy to spot honest mistakes among deliberate acts of plagiarism. Some people ITT call it murky, but I disagree, most cases are pretty clear.
As I've mentioned in the OP, these are not the cases I'm talking about, I'd classify this as a simple mistake and yes, they're fairly easy to spot.
Sure, mistakes can happen with regards to moderating, but once it's laid out in the open and looked at by many people, I think almost everyone would agree that it's a simple case of posting a quote and genuinely forgetting to add the source.
If I post this:
Imitation is the sincerest form of flattery
I would think that just having the quotes there would be enough to discount it from being plagiarism. It's also perfectly logical to have the quotes there, since, well, you're posting a quote...
Should I add a source to that quote? Or would that be fine without it? I'd think it would be fine without it, although I'd argue that adding it is just a bit more polite to do, so:
Source: Charles Caleb Colton