Ideally, after writing marketing plans for a few years, you can sit back and review a series of them, year after year, and check the progress of your company. Of course, sometimes this is hard to make time for (;there is that annoying real world to deal with);, but it can provide an unparalleled objective view of what you've been doing with your business life over a number of years.
Running a business certainly can not be separated from the purpose of doing business is to achieve profit. In an effort to achieve profit, have you had a good marketing plan? Or it turns out your business is running in place without any clear management.