I think this question is allowed here.

I’ve always been taught that Trench Warfare is slow and nasty. That one side would shoot bombs on the other side, than rush their soldiers to the other side and try to take over their trench. Although, they would get slaughtered in No Man’s Land

Instead, couldn’t one side just slowly dig closer to the other trench? Making No Man’s Land smaller and shorter? Wouldn’t this be easier to set up things to hide behind from bullets, thus making it easier to get to the other trench?