The origin of news production processes has not been extensively researched. This study identifies the factors that influence journalists' preferences for certain newsgathering channels to others at the genesis of news production: (1) the type of newspaper; (2) the centralization of the newsroom; (3) the story selection autonomy of the reporter; and (4) the specialization of the reporter in the topic of the story. During a six-week period, this study investigates the daily output of 20 domestic news reporters from the four main Flemish newspapers (N = 578). A multi-method approach was adopted, combining content analysis, reconstruction interviews with the reporters, in-depth interviews with their superiors, and newsroom observations. The findings show that stories from centralized newsrooms and non-specialist reporters, along with stories assigned by superiors, are more likely to be triggered by stories from other news media. For their part, stories from decentralized newsrooms and specialist reporters, as well as stories initiated by reporters themselves, are more likely to depart from classic routine channels such as press releases.