ICC wanted "consistent" conditions through the 100 overs of a game, in order to be fair to both the teams. "We would be providing pitches which give both teams equal chance. The pitches will be such that they do not change much during the course of the match. No team will have an advantage by bowling first," Dave Richardson said.

from Times of India https://timesofindia.indiatimes.com/sports/cricket/icc-world-cup/is-toss-the-real-boss-in-this-world-cup-so-far/articleshow/69627608.cms