Vespine wasps are overwhelmingly diurnal, navigating by daylight landmarks. The European hornet is an exception: workers continue hunting well after sunset and are strongly attracted to artificial light, blundering against lit windows and entering rooms. Nocturnal activity extends the foraging day and may reduce competition with day-flying wasps.
Size helps. Larger insects have larger eyes with better light-gathering, and hornets are among the biggest vespines. Their prey includes moths and beetles that are themselves night-active, so the schedule pays.
Hornets carry an unearned reputation for danger. Their venom is not exceptionally potent by wasp standards, and because a hornet is large the volume injected is greater, but the species is markedly less prone to defend food or approach people than a yellowjacket. Serious incidents almost always involve disturbing a nest. In Germany the species has been legally protected since the 1980s, a status granted precisely because its reputation drove needless destruction of nests.