hey
u know thats such a good question and im sorry i dont have a clear cut answer
my only advice is that they all were very under planned
somme was the worst with a HUGGGE loss of life (and first time tanks were used) the brts thought the war was gonna be won at somme (how wrong they were)
but yeah, all just big attacks that went bad
good luck
hopefully more ppl will help u out on this one
see ya