Venus & the Bright Planets
A brilliant, still point of light low in the sky — most often Venus, the single most-reported 'UFO' in history.
Tell-tale sign
A very bright, non-blinking light that stays in roughly the same spot for a long time and doesn't move across the sky like an aircraft.
What you see
An intensely bright 'star' — far brighter than anything around it — usually low in the west after sunset or the east before sunrise. It can look silver, gold, or slightly colored, and it holds its position for tens of minutes to hours.
Venus is the usual culprit, bright enough to cast shadows and to be seen in daylight if you know where to look. Jupiter, Mars, Saturn, and occasionally Mercury are fainter but still catch people out.
Why it fools people
Near the horizon, light from a planet passes through thick, turbulent air. That makes it twinkle, flash colors, and appear to shimmer or pulse. Our eyes also invent motion for a bright point against a featureless dark sky — the 'autokinetic effect' — so a fixed planet can seem to jump or drift. And because a planet is so far away it shows no parallax as you move, it can appear to follow your car, the same way the Moon does.
Because it's so bright and behaves unlike a normal star, people often report a hovering craft that 'paced' them or 'darted' when they looked away.
How to confirm
Check where the bright planets are: any planetarium app, or this platform's Identify and Sky Tonight tools, will tell you if Venus or Jupiter was in that exact direction and altitude at that time.
If the light stayed put for a long time, didn't have blinking aircraft lights, and sat low in the west after dusk or east before dawn, a planet is overwhelmingly the most likely answer.