"When I wasn't offered a contract, it was an easy decision for me," Arians said.
Arians said he was told he wasn't wanted back for a sixth season, but Steelers president Art Rooney II didn't give him a reason why.
"I can't answer that question," Arians said. "Only the people there can. That's the business. I know the job we did as a staff. I don't have any regrets."