The midfielder finalised a move back to Pittodrie on Wednesday after spending the past three-and-a-half years at Plymouth Argyle.
He spoke to Kilmarnock regarding a return to the SPL and reports suggested Clark was ready to agree a deal to head to Rugby Park.
However, Aberdeen stepped in with a late offer and the 30-year-old acknowledged he could not decline the chance to play for the club again.
"I had a good chat with (Kilmarnock manager) Kenny Shiels," said Clark in the Daily Record.
"I have a lot of respect for him and I appreciated Killie's offer, but the chance to return to Aberdeen was too good to resist.
"It totally made sense for me to come back as it's my home town and I still have a home there, so it was the right move after three-and-a-half years in England."
Source: Team Talk
Source: Team Talk