Direct quote 1997
“even in normal conversations, the protagonist should have his gun at the ready, finger on the trigger. He must be cautious about not mistakenly firing his gun and killing an innocent person—yet at the same time, if he's too slow in deliberating he risks being killed himself.”
What it documents
Kojima explained that in a typical command adventure time stops while the player decides what to do, so it is not “real-time” in any sense; looking for a way to make that kind of game feel more real-time, he arrived, in Snatcher and Policenauts, at the idea that the protagonist should always have his gun at the ready, finger on the trigger: he must be cautious about not mistakenly firing his gun and killing an innocent person, but if he deliberates too slowly he risks being killed himself, and thus he tried to restore a sense of tension and excitement to the adventure.
Source
shmuplations.com; "What is Game Design?" roundtable in Game Hihyou magazine, unofficial English translation, 1997 (Kojima's contributions). View source ↗
“After searching for a way to make that kind of game feel more "real-time", I came to this idea for Snatcher and Policenauts”