If you applied to UW School of Medicine and were not offered an interview, you are likely missing something in one or more of the following:
Motivation: You may have told us what got you interested in medicine in the first place. That was your inspiration. Take that to the next level and tell the screeners what keeps you interested and why you are drawn to a career in medicine. Inspiration is the first step in motivation, but motivation should also be informed by additional exploration and life experiences to show that you have gone beyond "wow…that's amazing" to thinking about how and why medicine might be gratifying for you.
Clinical Exposure: The screeners are trying to assess your understanding of what you are getting into, both positives and negatives about being a doctor. Your understanding can be demonstrated through what you write about your exposure to doctors and what you learned shadowing them. If all you learned was procedures or that all doctors are dedicated, your reflections aren't sufficiently nuanced. When you just include a list of who you shadowed, we have no way of assessing your understanding.
Service: The practice of medicine requires dedication and a willingness to be there for someone else. We expect to see a consistent record of service over time, not just one service activity completed as part of an organization- like staffing a fund-raising event. We also expect to see some reflection of how you were affected by helping others or seeing what they were struggling with.
Academics: Check out the MCAT/GPA tables on the AAMC website. They show data concerning the academic metrics associated with being admitted, passing licensure exams, and finishing medical school. These charts are based on the "old MCAT", but if you took the "new MCAT" you can convert your percentile score into an "old MCAT" score and see where your metrics fit.
Leadership: Think about whether you have engaged in leadership in the form of heading a team, responsibility for others, organizing something, adding an important idea that facilitates change in an organization, or starting something new. The screeners would like to see what you learned from being a leader as well as what you think makes a good leader. Was there anything difficult for you being a leader?
Letters of Recommendation: It is unusual that a letter of recommendation says something negative. Most are good; some are glowing. Therefore, it's rare that letters weigh heavily on a screening decision.
In summary, you need to write clearly about what you've discovered to make the case to others that medicine is a well-thought out career choice. Schools are looking for reasons that your goals can only be accomplished if you become a physician. For example, if you mention the privilege of helping people improve their lives, tell us why you have to be a doctor to do that, rather than a teacher, minister, social worker, or nurse. In what unique ways do doctors help people improve their lives?