Last year, as it worked to fend off Elliott’s campaign, Southwest executives argued that customers flocked to the airline specifically because they can check their luggage, golf bags, skis and musical instruments for no charge.

Executives cited an analysis by a consulting firm that determined bag charges would bring in at most $1.5 billion in revenue a year, but cost the airline $1.8 billion in lost market share. Free bags ranked just behind price and schedule among the top reasons travelers pick Southwest, executives said then. “Changing our bags policy would be value destructive,” said Ryan Green, who was then in charge of the airline’s transformation strategy, at the airline’s investor day in September.

Board members were skeptical of that conclusion, according to people familiar with the matter. Some of them had experience at airlines that charged for bags. And where else would customers go, they reasoned?