Self-return is a quality of a person, manifested in the activity with the maximum application of effort, knowledge, skills, and mental strength. Depending on the scope of the actions performed, one distinguishes how self-giving manifests itself in work and love, in serving the homeland and playing, mastering the new and improving the existing one. Such an application of own forces at maximum speed is somewhat comparable to self-sacrifice, but has a limit of manifestation, then self-sacrifice has no boundaries (or rather, death can be its limit, as the stopping of all processes).
Self-return is an activity at the limit of one’s own abilities, produced unselfishly and, of course (here one can speak of sincere love or passion for work). Naturally, it implies a certain sacrifice for the sake of a chosen idea or person, but such sacrifice still has reasonable limits (guided by this feeling, you can give all the savings, but not life, time to sleep, but not half of the organs).