The 28-year-old fell down the pecking order during his time with the European champions and opted to return to the RheinEnergieStadion, where he eventually suffered relegation in 2012.
And Podolski believes his decision to leave the Bavarian giants had a negative impact on his career.
"I believe that if Jupp Heynckes (Bayern interim coach) had arrived one or two weeks earlier in 2009, I would probably still be at Bayern now," he told Bild. "He was desperate to keep me.
"From a purely sporting perspective, returning to Cologne was certainly not helpful."
Podolski was linked with a move away from Arsenal in January after failing to break into the starting line-up following his recovery from injury, but the 28-year-old never envisaged leaving the North London club.
"There was absolutely no truth in it," he asserted. "The coach (Arsene Wenger) told me as such, and I knew there was no truth in it."
Arsenal are set to meet Bayern in the last 16 of the UEFA Champions League, with the first leg to take place at the Emirates Stadium on February 19.
