Who couldn't predict the movement of planets accurately?

Historically, astronomers like Claudius Ptolemy and even Copernicus struggled to predict planetary movements accurately due to their reliance on geocentric models and the lack of precise observational data. Their models often involved complex systems of epicycles to account for observed planetary motion, which were ultimately insufficient. It wasn't until Johannes Kepler applied his laws of planetary motion, based on Tycho Brahe's detailed observations, that a more accurate heliocentric understanding emerged.