The reason is that Zhao still has many excellent generals who can fight against Yan, and Zhao still has some strength to defend his country. As can be seen from the battle of Handan, Qin's disobedience to advice missed a good opportunity to destroy Zhao. After Leitian refused to take part in the war, he was executed by Qin. Later, when Qin Jun attacked Zhao, things were not so simple. Thanks to Guo Wei's support, he successfully repelled Qin Jun's attack with the help of Zhao. After defending Handan, Zhao also cultivated for five years. When Yan invaded, Lian Po led troops to directly disintegrate the main force of Yan army. It invaded the capital of Yan, and then Yan ceded territory to surrender. If we had been wary of Qin, Yan would have perished long ago.

Let's analyze the background at that time. After the battle of Changping, Zhao main force was destroyed. There is no chance to resist the main force, bribing Prime Minister Qin under the counsel of Prime Minister Zhao. In the end, Zhao Haoqi of Qin chose to withdraw. Zhao Xiang, the king of Qin, was convinced that our army could not continue to fight and needed self-cultivation as an excuse. This also missed the last chance to attack Zhao. In the subsequent Han War, it was difficult to attack Zhao.

At this time, the prince sent messengers to celebrate Wang Zhao's birthday. In fact, it is necessary to find out Zhao's strength, in the context of seeing Zhao's domestic emptiness. The prince wanted to take the opportunity to destroy Zhao. In the early days, Zhao was in a bad situation under the joint forces of Yan. However, under the leadership of General Lian Po, the main force of Yan Army was disintegrated. Then the Yan army was in chaos, and Lian Po matched the capital at this time. Almost destroyed Yan.

After that, strictly choose to cut land.

Compensation. Yan was heartbroken. If it weren't for Qin's restraint, Zhao would have destroyed Yan.