The England international moved to Eastlands on Tuesday in a shock £12million deal after spending 12 years at the midlands club.
After intensive speculation that he would join Liverpool last summer, few predicted that Barry would go elsewhere, if anywhere, this year with the Merseyside club reportedly still interested this time around.
However, Barry did not want a long-running transfer saga this summer as he suffered last year, and revealed to Villa fans his reason for joining the Eastlands revolution.
"Once I had spoken to (City manager) Mark Hughes there was nowhere else I wanted to go. I was also desperate to avoid any long, drawn-out saga," Barry told the Birmingham Mail.
"I feel I am joining a club that will seriously challenge to win major honours.
"People might doubt that but I am convinced, with the plans the club has short-term and long-term and the backing the manager will receive from the owners, that we will be a major force.
"I have honestly been very undecided what to do, the (Villa) manager (Martin O'Neill) and the whole club have bent over backwards to try and persuade me to stay and made me a fantastic offer, which I am extremely grateful for."
He continued: "I need a new challenge, I have a massive fear of going stale and falling into a comfort zone.
"I believe the deal is a good one for the club. I am sure the manager will use the money well to strengthen the team and the club will go from strength to strength. I am also excited now about my new challenge."