Since in Northern Hemisphere, winter solstace (Yule) is the shortest day of the year and the longest night. Lighting a candle, or lots of them, helped to remember that there is hope that the light will come the next day. A lot of the old beliefs have some variation of the same theme.

Why it is not working for you is that maybe you know the light is always there with our artificial lights in our houses, cars, work areas, and places where we feel secured.

Next year, turn off all the lights in the house, or better yet (an you are bundled) be outside when you light that candle, yule log, etc. Think of our ancestors were hundreds of years ago when the tradition came about to celebrate the light. Maybe then, it will become real.