Tricycle.com is no doubt one of the absolute best online resources and supports for your spiritual practice. They have such a wealth of information available on the site and every day there is something new and insightful to read. The other day I came upon this article about evaluating your meditation practice. I realized that I evaluated mine in a vague sort of way, with no real direction or criteria, but Gil Fronsdal lays out some really specific ways to look at your practice, which are very helpful.
Our motivation can be to awaken and cultivate beautiful qualities of the heart and mind—love, peace, courage, compassion, insight, understanding, the pursuit of the truth and liberation. Developing these qualities does not need to be for oneself. Sometimes my primary motivation to practice has been not for my own sake but for other people. In fact, I believe that if you do it only for yourself, you are unlikely to sustain your motivation over many years. A significant way to fuel meditation practice is to do it with the wish that it will somehow benefit others as well as yourself.
There are long-term and short-term motivations. Experiences of realization may be worthy long-term goals, but in the short term it can be useful to have modest aims such as cultivating small but noticeable improvements in concentration, nondistraction, compassion, or patience, as well as small, immediate movements toward letting go and experiencing freedom. I have found there is a beautiful way in which practicing with immediate, realistic goals allows for a steady maturing into some of the more developed areas of meditation practice.