Stupidity.

Once I had a friend with a huge lack of intelligence. We were used to play RPGs and he created a character supposed to be intelligent.

I always told him that you can fake stupidity if you're smart, but never the opposite.

My granny (good soul, RIP) was used to say "you can't extract lemon juice from a turnip".

So, whenever I find myself back to the start, I don't have to blame stupid people but only myself on having high expectations from low brains.

Mea culpa, mea maxima culpa.

If I continue to hit my head against the wall, I'll end up with an aneurysm, not just a headache...