Speaking to the Los Angeles Times, the director admitted that the 2009 blockbuster failed to live up to expectations.
"It was kind of a mess, wasn't it?" Bay said. "Look, the movie had some good things in it and it was entertaining and it did very well, but it also failed in some key ways. I learned from it."
The 45-year-old, who also helmed the first Transformers movie, blamed the Writers Guild strike for the problems with Revenge Of The Fallen.
"We got burned on the last movie," he commented. "The big thing was the writers' strike, it hurt the film and it made it hard on everybody. We had three weeks to get our story and, really, we were going into the movie without a script. It’s tough to do that. It was too big of a movie. There were too many endings or too many things that felt like endings."
Bay is currently working on the third robot blockbuster Dark Of The Moon, due for release this summer, and assured that the movie will go "back to basics".
"I absolutely believe this is going to be a much better film than the second one," he said.
> Click here to watch the trailer for Transformers: Dark Of The Moon