Why is the detection of a star floating in the absolute blackness of intergalactic space so profoundly difficult for astronomers?

It is a tiny, dim pinprick against an almost perfectly black canvas with virtually no background light

The primary difficulty in counting rogue stars lies in the lack of contrast against their surroundings. Stars within a galaxy benefit from the collective glow of their neighbors, providing some degree of background illumination to aid detection. Conversely, a star adrift in the true void of intergalactic space lacks this supportive glow. It exists against an almost perfectly black backdrop, meaning its faint light signal has virtually no contrast, rendering it exceptionally difficult to spot compared to stars still within the gravitational embrace of a major structure. This observational challenge leads to a bias where only the brighter rogues or those near galactic halos are currently sampled.