A media list decays every month. Journalists change desks, publications close and a pitch sent to somebody who left two years ago costs a relationship rather than merely failing, so maintenance is the work rather than an afterthought.
Embargoes are precise instruments. A time, a title and who agreed to what has to be recorded exactly, because one early publication damages every other relationship on that story at once.
Retainers overrun invisibly. Ten unlogged phone calls a month is a day of somebody's time, and an agency that discovers this at renewal has already given the work away for a year.
Coverage vanishes if it is not captured. Broadcast clips and online articles are edited or removed, so recording them as they appear is what makes a quarterly report possible at all.