The anticipation of future outcomes and the expectation of success based on experience in setting and reaching successive subgoals are the two sources of motivation. When subjects have an opportunity to set such subgoals and to evaluate their performance, performance tends to improve.
Observation and vicarious reinforcement or no reinforcement at all may lead to the acquisition of learning. It is the expectation of reinforcement that leads to the performance of learning. The expectation of reinforcement can develop from observing the consequences either of others' behaviors or of our own behaviors.
Human behavior is guided largely and is kept consistent by anticipation of self-approval or self-criticism, both of which evolve out of personal standards of behavior that are based on the standards of socializing agents, like parents and peers.
New responses can be learned vicariously and without either actual or vicarious reinforcement. Human beings' cognitive skills enable them not only to reproduce observed behaviors but also to create new and original behaviors out of combined observations.