Another word of advise if you are meditating in an attempt to reach Liberation and not just for it's health benefits. You must be your system before anything else in your life. Say you do Kriya Yoga, and you are a painter for a living, you are not a Painter who does Yoga, but must be a Yogi who paints for a living. It has to become the foremost aspect of your identity, however that does not mean you go around telling everyone about it, only on the personal level, it will have the most influence on decisions you make in life and the like.
There is no consistency is the small amount of dabbling I have done meditation wise, but I feel the opposite here. While I understand your logic, for me I look at it similar to eating healthy, or working out. If I want to live a healthy life I am going to eat healthy foods all the time not some of the time, otherwise I know I am hurting my health. And while I might be ripped today, if I dont keep working out I will be back to out of shape in no time. Easier said than done, but I do think it should be done with consistency if possible.