SPL chairman Lex Gold invited six managers to discuss possible changes to the top-flight game earlier this month, with another meeting due to be held in January.
Gold later asked Jefferies to attend but Jefferies refused to go. "You would have to ask Lex why I wasn't there," Jefferies said.
"Maybe 20 years' experience in the game isn't the right requirement for Scottish football.
"When I got a call from Lex to invite me in the back door he said he didn't think it was my cup of tea - which was a strange comment.
"My view is all 12 managers should have been there.
"I wasn't going in the back door. The experience I have isn't enough for Lex so I'll leave it at that."
Jefferies added: "It was also said they would refer back to the other managers, but I haven't heard from Lex."