Here it is not about individual techniques but basically about the representation of two process qualities within meditation. While both are not independent, one of them is at the beginning: 1) Meditation as an intention, goal, projecting within one's own values, one's own self-image, to strengthen one's self. This type of meditation, performed in exercises, efforts, etc., is logically at the beginning of meditative activity. It is somewhat exhausting because it means a change in the course of the day, but in another way it also psychologically stabilizing because it does self-assertive - and by the nature of the exercise brings also relaxing, liberating aspects, etc..
A natural limit is that this type of meditation - of "intention to meditate" - is limited by one's own inner "world," as stated above. Of course, individual exercises can be performed perfectly within the limits.

2) Meditation without intention, which comes to one who is unintentional. This type of meditation does not "fit", findings come "unasked", sometimes questioning one's own life achievement, it can completely change one's attitude towards things "with one breath". It can occur at any time - in the most strenuous everyday life, at night, in sleep, in a dream.