The idea that war is won by technology is a common mistake that has taken root in the US. Wars are not determined by how many casualties a side can inflict. Rather wars are determined by how many casualties a side can take and keep fighting. Although the Saudis have more high tech weapons than the Houthis, the Houthis have morale on their side. They are fighting to defend their homes and families. They cannot afford to back down. Saudi troops are far less motivated, and many of them are likely unsure why exactly they are fighting.