Perhaps it was considered as bad wasting...
Perhaps it was considered as bad wasting, which was prohibited, so “the feet” were coupled to “the heads”, which were to be wiped, not in order to be wiped but just to draw the attention to the necessity of economizing in pouring water over them.
It was said “ to the ankles ” as an end of washing in order to clear the meaning for those, who thought that the feet were to be wiped, because no end was determined for wiping in the Sharia.” This philosophy of coupling “the feet” to “the heads” and in mentioning the end (limit) of washing the feet had nothing to do with deducing the legal verdicts out of the verse at all.
The verse had nothing of that at all but it was his way in submitting the verse to his doctrine instead of deducing the legal verdicts out of the evidences the verse had. He was so odd in his affectation, which no one would listen to except who thought that washing the feet was irrefutable according to one’s belief but as for it was the point of the dispute then no one would listen to because many of the Sunni had confessed that the verse declared the obligation of wiping the feet.
The rules of Arabic determined that “ your feet ” was coupled to “ your heads ” which must be wiped according to the consensus, and this sufficed as clear evidence. A look at the traditions of washing The traditions talking about washing the feet were two kinds: The traditions that didn’t evidence washing like the tradition narrated by Abdullah bin Amr bin al-Aass and mentioned in al-Bukhari and Muslim’s Sahih s.
He said: “In one of our travels with the Prophet (s), the Prophet (s) retarded a little. Then he joined us when it was the time of Assr prayer. We began to wipe our feet (in wudu’). He said: Woe be to the heels from Hell!”[^10] If this tradition was true, then wiping the feet would be the correct act of wudu’ because the Prophet (s) didn’t deny it but he confirmed it. He only denied the filthiness of the heels.
Among the Muslims were ignorant bare-footed nomads, who often made water over their heels especially in travel, so he threatened them of Hell lest they offered prayer with those impure heels. The traditions that referred to washing the feet in wudu’ like the tradition narrated by Hamran the freed slave of Othman bin Affan.