This wonderful, one minute mitzvah, is incredibly powerful. It asks us to stop and take note of the ways in which we create stumbling blocks and obstacles for others and ourselves unconsciously, all the time. Mitzvahs are not only here to protect and care for others, they are wake up calls. They ask us to become aware, to recognize what's going on, and to take a moment to stop and change our action, thoughts or words. 
And what a moment it is. Although we may not realize it, these are atomic, powerful, unfailing directions. They guide us through confusion and fog to bring light and clarity into the day. They heal our confusion. Doing this particular mitzvah asks that we become aware of what is a stumbling block and how we actually create them. As we recognize that,  it's easy to stop. And to protect and to heal all lives.