If one of your go to behaviours includes being  motivated to act simply based on your own enthusiasm toward getting things accomplished, you are self motivated.

In essence this means you would typically  be demonstrating  a high level of initiative, that is the ability to assess and start things independently.

Self Managing

Leaders seek people to join their groups who both act without being asked or told (initiative) but also can self manage, that is being fully responsible for thier actions.

Peoples behaviour will always create an  impact and without acknowledging and accepting responsibility for that impact (i.e., outcomes) of your behaviour there is a higher risk of bad behaviour (i.e.,  you don’t worry about the results, it is someone elses responsibility).

Initiative alone, without self management, can produce unexpected and even unwanted results.

Oversight

Demonstrated initiate coupled with satisfactory self management can result in a high performing team or group.  The hands off style of leadership can be very effective with these teams, and micro-managing can be detrimental.

The teams productivity is high because the work self motivation typically results in a high level of personal satifaction by those that practice it.

One failing I often see with hands off management of highly motivated groups is the mistaken belief that given the skills and abilities of the group members oversite is not needed or can be a minimal levels.

Granted one of the benefits of self motivated, self managed teams is that direct oversight is not needed.   This does not mean leaders and mangers do not need to be well informed.