Ranks exist to help divide the syllabus into manageable chunks. They break up learning into achievable and quantifiable sections and give you direction. Ranks also serve to boost confidence in certain areas of competence. They provide a way of knowing what you know, and what you are still working on. They also help motivate you towards a goal. Which has to be one of the best reasons for them to exist.
Life gets pretty busy, and over the years, many things will try to take the place of your training time. But if we have our goals clearly laid out, and we stay focused, we can push through the distractions and keep our learning on track. So set your next assessment date and work out how many classes you can make between now and then. Work out your additional practice times too and get serious about achieving that next rank.