In a perfect world, we'd all have the same information, and stocks would price themselves quickly and accurately, and there'd be no "mystery" or uncertainty in taking a position.
Then again, there wouldn't be any massive opportunities like the one I'm going to show you, either.
This is the next best thing to getting something for nothing. The situation isn't unlike what used to happen in stores back in the day, before barcodes and RFID tags, when a high school kid would go around with a sticker gun, sticking prices on items, and make a mistake.
It might not have been so great for the employee, but it was always a sweet feeling to get an unexpected deal.