Answer by taking a quote from the following article:

Armando Anthony "Chick" Corea (born June 12, 1941) is an American jazz pianist/electric keyboardist and composer. His compositions "Spain", "500 Miles High", "La Fiesta" and "Windows", are considered jazz standards. As a member of Miles Davis's band in the late 1960s, he participated in the birth of jazz fusion. In the 1970s he formed the fusion band Return to Forever.

In the early 1970s, Corea took a profound stylistic turn from avant-garde to a crossover jazz fusion style that incorporated Latin jazz with Return to Forever. Named after their eponymous 1972 album, the band relied on both acoustic and electronic instrumentation and drew upon Latin American styles more than on rock music. On their first two records, Return to Forever consisted of Flora Purim on vocals, Joe Farrell on flute and soprano saxophone, Airto Moreira on drums , and Stanley Clarke on double bass. Drummer Lenny White and guitarist Bill Connors later joined Corea and Clarke to form the second version of the group, which expanded the earlier Latin jazz elements with a more rock and funk-oriented sound inspired by the Mahavishnu Orchestra, led by his Bitches Brew bandmate John McLaughlin. This incarnation of the group recorded the album Hymn of the Seventh Galaxy, before Connors' departure and replacement by Al Di Meola, who was present on the subsequent releases Where Have I Known You Before, No Mystery, and Romantic Warrior.  Corea's composition "Spain" appeared on the 1972 Return to Forever album Light as a Feather. This is probably his most popular piece, and it has been recorded by a variety of artists. There are also a variety of recordings by Corea himself. These included an arrangement for piano and symphony orchestra that appeared in 1999 and a collabration with vocalist Bobby McFerrin on the 1992 album Play. Corea usually performs "Spain" with a prelude based on Joaquin Rodrigo's Concierto de Aranjuez (1940), which earlier received a jazz orchestration on Davis and Gil Evans' Sketches of Spain.  In 1976, he issued My Spanish Heart, influenced by Latin American music and featuring vocalist Gayle Moran (Corea's wife) and electric violinist Jean-Luc Ponty. The album combined jazz and flamenco, supported by Minimoog backup and a horn section.

why did he decide to change