Ridge, speaking Tuesday at a forum that included several other former Homeland Security officials, described the internal debates over handling the color-coded warning system.
"More often than not we were the least inclined to raise it," Ridge said, according to a report in USA Today. "Sometimes we disagreed with the intelligence assessment ... There were times when some people were really aggressive about raising it and we said, 'For that?'"
The risk level was raised if a majority of the members of the Homeland Security Advisory Council agreed and the president concurred, USA Today said.
Local authorities often chafed at the raising of the alert level, saying it was expensive to put on additional personnel such action demanded.
Ridge resigned as Homeland Security secretary Feb. 1. He has been replaced by Michael Chertoff, who said he is considering changing the color-coded alert system.
The threat advisory is currently at the yellow -- elevated -- section, the middle of the five-tier alert program.