Reflection is a way of measuring. We can use reflection to measure how we look, where we've been, progress on a project etc. The ability to review our work and ourselves is important. We use this time to make adjustments. If something's not as it should be, we must be able to notice and make a correction. Similarly, if we are working on a large project, we must be able to step back to see the full picture.
It's only by reflection that we're able to see where to add and how close we are to our vision. Reflection can be both difficult and rewarding. Yet, doing so helps us see the truth--what's real, and what exists only in our minds.