Garcia did not have his contract renewed after the World Cup and, in his first interview since, blamed the team's medical staff for setbacks that he claimed led to an unconvincing tournament, even if Belgium got to the quarter-finals.
"We put our World Cup at risk due to certain injuries and illnesses that were not handled correctly," he told the Brussels newspaper Le Soir on Monday.
Belgium started the tournament in unimpressive style with draws against Egypt and Iraq before a 5-1 win over New Zealand in Vancouver helped them top their group on goal difference. They then had to come back against Senegal to advance to the last 16, where they had their best game of the tournament against the United States.
Manchester City winger Jeremy Doku was expected to be a key part of the campaign, but struggled with illness and ended up in the emergency room during the World Cup with fluid on his lungs.
"A week earlier, at my insistence, we had managed to arrange an appointment for a scan," Garcia said.
"The doctor didn't think the scan was necessary because he had given Jeremy antibiotics. Jeremy felt better and ultimately didn't want to go himself either. But six days later, he spent the night in the emergency room."
Other injuries
Garcia also cited the injuries of captain Youri Tielemans, Charles De Ketelaere, and Zeno Debast during the tournament. There was no immediate reaction from the Belgian football association.
But Garcia felt, despite the setbacks, he did a good job in the post and repeatedly emphasised in the interview that he left without resentment.
"I came for a mission. I took Belgium under my wing because a World Cup was approaching with Kevin De Bruyne, Thibaut Courtois, and Romelu Lukaku," the manager said.
"I thought that those three legends could still carry Belgium and that we could guide them as far as possible together.
"My mission ended when the World Cup ended. We experienced some very beautiful things together."
Garcia said had he been offered a contract renewal, he might have stayed.
"I think I would have liked to stay, but that would also have been a choice for comfort on my part," he added.
"I knew the squad, we had worked together for 18 months, and I had grown attached to the players and the country.
"I don't think it is immodest to say that we have put Belgium back on the map of world football. So my mission has been accomplished. And then it is good to move on to something else. I left without bitterness. Today I am very calm and satisfied with what I have done."
Belgium moved speedily after the World Cup to appoint former Dutch international Mark van Bommel as coach.