If you are on spiritual path, a keen watch on you being practicing defined guides is an Introspection.

If you accept and follow Karmic path, cleverly accepting yes as yes and no as no for either your material or immaterial wants or desire, it is an Introspection.

Your mind when works right for all right achievements and when it follows all practicised thoughts either as an experienced follower, or a persona being or as a blind spectator and if all are for right purposes clearly defined or undefined in spiritual paths it is an introspection.

Your soul / your presence when is alert about what to be done for purity, right achievements and correct happiness as required to be done or carried out for accepting a presence, a truth, a reality is an spiritual introspection.

When you set your Goals, define it’s path about how to achieve these goals or when you collect the information about how these goals has to be get achieved from well practicised and applied presence or available facts; keeping an eye on whether the defined or collected practices is properly getting followed or not, what more improvements is further needed, molding own self and required activities to exactly fit with the need, requirement and to match is an Introspection.

An awakened and a continuous watch on your own self and its being engaged in right kind of activities is an Introspection.