Originally Posted by
Steely Glint
They deployed their infantry *outside* of the castle. Like, why even have a castle if you're going to do that? Then when they got their kicked and a bunch of soldiers killed for no reason they retreated inside the castle anyway, meaning the only thing deploying outside the walls achieved was that then had to light the trench during the fighting, which would have failed completely if Melisandre hadn't turned up.
The Dothraki Suicide Charge can be written off as a simple miscalculation (It's not like worse mistakes haven't happened in real history), but their entire deployment at the start was the work of a complete madman.