Lucid dreaming is so powerful because it helps with your waking life by relieving anxiety, improving your motor skills, enhancing your problem-solving skills and increasing your creativity.
Relief from anxiety
By realizing that you are actually dreaming, you can be in control of your dreams. This means you can have control on both development and ending of your dreams. This comes particularly handy for people who have nightmares regularly.
Improvement in your motor skills
Some studies suggest that you can actually improve your motor skills, like for example snapping your fingers, by 'practicing' during your lucid dream. Apparently, the area of your brain triggering the physical movement of the fingers is also triggered if you are dreaming about it.
Better at problem-solving
According to a study, lucid dreamers are more intelligent and better at problem-solving than people who don't lucid dream (1). In the study lucid dreamers and non- were given some problems to solve. People who lucid dreamed were able to solve 25% more problems than those who didn't.
More creativity
Other studies show how lucid dreamers are more creative than the average person (2).
References
1. Bourke, P., & Shaw, H. (2014). Spontaneous lucid dreaming frequency and waking insight. Dreaming, 24(2), 152–159. https://doi.org/10.1037/a0036908
2. Blagrove, M., & Hartnell, S. (2000). Lucid dreaming: associations with internal locus of control, need for cognition and creativity. Personality and Individual Differences, 28(1), 41–47. https://doi.org/10.1016/s0191-8869(99)00078-1