The 33-year-old was named the best player in world football earlier in December after leading Croatia to the World Cup final and helping Real Madrid win their third consecutive Champions League title.
"I cannot speak why someone didn't turn up at an award ceremony. It's their choice," Modric told Sportske Novosti, as quoted by ESPN. "It doesn't make sense, does it? It seems these votes and awards are only significant when they win it.
"It's unfair to fellow players and voters who have nominated them in the past 10 years, as well as to football and the fans. However, people will act the way they think they ought to.
"In my opinion, things are very simple: Ronaldo and Messi are phenomena who have been dominant in the past 10 years or so. They've been in a league of their own. But we are talking about a season's accomplishments here and I guess it means something that votes by national team coaches, managers, football legends, journalists, and fellow players have produced the same results."
Modric thinks he knows how to attract Messi and Ronaldo to future ceremonies, though. He joked: "If the debate is going to be about how good a particular player is, the only course of action is to award all trophies to Messi and Ronaldo until they retire and scrap the voting."
Modric is the first "other" player since Kaka in 2007 to win football's greatest individual honor.