Xerri is leaving Canterbury for Melbourne Storm on a three-year deal, a move presented as the fresh start he needs.
After being dropped following the Bulldogs' Las Vegas opener, he reclaimed his starting place in round six and scored just two tries in 11 games.
He discussed his season on Josh Mansour's Unscripted Podcast.
"The year before, I was battling an injury, osteitis pubis; I was playing on it," he said.
Xerri said he rested in the off-season, travelled to Lebanon, ate poorly and entered pre-season without preparation.
He was underdone and joined the team only three or four weeks before the trial, when Cameron Ciraldo assigned him to the right side, despite his career as a left-side player.
Reports described Xerri as unhappy and alleged he was complaining; after news of his dropping emerged, he and Ciraldo worked out who had leaked it.
Xerri said neither he nor Ciraldo had spoken to the press.