The Villans made the latest move in a series of questionable decisions on Monday, firing manager Roberto Di Matteo after just 124 days in charge.
Despite Di Matteo spending £34 million on players over the summer, the Italian left his job with Villa just two points clear of the relegation zone after 12 games.
The Championship side have now gone through more managers – six – than wins recorded – four – since the start of last season, and it appears there are serious problems behind the scenes at Villa Park.
And Redknapp believes the first problem was firing Tim Sherwood, who was dismissed at the start of last season despite keeping Villa in the Premier League and sending them to the FA Cup final the season before.
“Getting rid of Tim Sherwood was a massive mistake,” Redknapp told Danny Kelly on Drivetime.
“I think they need someone in there given time. They can’t keep changing managers every six months or so, and that’s the way it’s gone at the moment.
“It’s sad, because they’ve got great support. Every week they’re there, the fans. They follow the team away, and they deserve better.”