Because each of them intended to visit the ancient House of God

Al-Nasa’i narrated on the authority of Abdullah, who is Ibn Masoud, who said that the Messenger of God, may God bless him and grant him peace, said, “Continue between Hajj and Umrah, for they ward off poverty and sins just as they ward off The furnace is the impurity of iron, gold, and silver.

There is no reward for the accepted Hajj other than Paradise, so in the beginning he made Umrah to Umrah, as well as Hajj and righteousness, and here he made Hajj and Umrah preceded so that there would be another reward from them, not what the first hadith gave, which is the banishment of poverty, so there is a barrier between you and your servitude if you combine Between these two acts of worship