They failed to bring up a book like the Holy Quran.

"In her book" Defending Islam, " Laura Vecia Vaglieri says:" How can this miraculous book be the work of Muhammad, the illiterate Arab? Although Muhammad called on the opponents of Islam to come up with a book such as his book, or at least with a Surah like its Surahs:

Although the people of rhetoric and the eloquent statements were not few in the Arab countries, no one was able to bring in any effect comparable to the Quran. They fought the Prophet with weapons, but were unable to match the Quranic superiority