Villa had a lot of success early on with enthusiastic cavalry charges. He brought a lot of charisma to his command, was an excellent horseman and an excellent judge of horses, and could add mobility to his already mobile troops by putting them on trains. It worked well against demoralized, badly-supported troops in scattered defensive positions in the initial period of the Revolution , with Villa, Carranza and Zapata fighting against Huerta. Villa was also lucky to have the assistance of Felipe Angeles ( perhaps the most heroic character in the Revolution), who provided expertise in artillery. In the latter phase, though, it was not enough. After the successes of 1914 and Huerta defeated, the Convention of Aguascalientes allowed Carranza to assume more power, and put him in position to get assistance from the US government. After this, supplies, infantry tactics, and fortification began to be a problem for Villa. This was starkly shown at the Battle of Celaya, where Obregon essentially used the same techniques being used in the European war, employing trenches, barbed wire, and machine guns. After this defeat, Villa was more or less a bandit leader on the run until he could negotiate a surrender in 1919.

Katz: The life and Times of Pancho Villa