When Zhuge Liang first made the Northern Expedition, his chances of winning were still relatively high. Because Cao Cao thought Liu Bei was dead, no one could threaten them. But when they let their guard down, Zhuge Liang suddenly launched an attack. At that time, Cao Wei was unprepared and caught them off guard. Moreover, due to the geographical location, Cao Cao's control over it was weak, so he did not send most troops to defend it. In addition, some generals in Zhuge Liang's army also have strong influence in the northwest. For these reasons, Cao Wei, Longxi and other cities surrendered one after another at that time, and Zhuge Liang's first northern expedition belonged to the winner.
But it is a great pity that Cao Cao learned a lesson because of this raid. After the defeat of the war, they strengthened their border defense. This way of surprise attack makes it more difficult for Zhuge Liang to fight again. Zhuge Liang is very cautious every time he decides to explore the north. At that time, the strength of Shu was weak, and there was not much mistake, because they really couldn't afford to be hurt.
There were victories and defeats in all previous Northern Expeditions, but except the first one, Shu suffered little losses in other wars. This also left a lot of room for Shu. If Zhuge Liang had chosen not to continue the Northern Expedition at that time, but to recuperate, Shu would not have perished during Zhuge Liang's reign, but no one in Shu could be as omnipotent as Zhuge Liang after his death. Once Zhuge Liang dies, the strength of Shu will be reduced a lot, and the soldiers will only accelerate the demise of Shu without correct operational strategies.