Aliens will likely never visit Earth due to the vast distances and limitations imposed by space and time. The universe is unimaginably large, with even the closest stars being light-years away—meaning light, the fastest thing in the universe, takes years to travel these distances. Since no object can move faster than light (as dictated by Einstein’s theory of relativity), any journey across interstellar or intergalactic space would take tens of thousands to millions of years, even with advanced technology.
Additionally, the expansion of the universe stretches space itself, further increasing these distances over time. Combined with the immense energy and resources required for such travel, it becomes highly unlikely that any civilization, no matter how advanced, could overcome these barriers to reach Earth. Time and space make interstellar travel not only impractical but, for all intents and purposes, impossible.