Sometimes I like to go on StackExchange, find questions I'm deeply knowledgeable in and where people are saying things like "it can't be done" and reply with a code example doing the thing.
I really don't understand how people can answer questions they are not 101% sure of the answer, on a public site like that. I mean, informal chat with a colleague? Sure. But to go on SO and do it, it's unthinkable for me.
If they're like me (I'm weird, but I think in this case it's likely), then they may be both confident and wrong at the same time.
My brain doesn't seem to index many examples of my own wrongness, even though I have more than once thought "this would be a good mistake to remember", and the worst that I can remember is under an NDA (very confident and very wrong), so the only example I can give is a currently ongoing personal error:
I've spent the last 5 years improving my German substantially, but the whole time I've been trying to estimate my current skill level and gotten the same answer, B1.
