The starting point .
Everything we do is a response to stimuli that generate impulses and inhibitions, either directly through 'habit' and 'instinct' or indirectly through feelings of 'want', 'need', and 'ought'. Understanding the causes of and interplay between these motivations is the key to understanding behaviour.
WHY A NEW THEORY?
None of the existing theories appear to capture the various aspects of motivation that we know to be important even from our everyday experience.

Some theories focus on choice and decision-making, others focus on habit learning, or on basic drives, self-regulation, social influence, identity and so on ... but any action at any one moment can arise from any or all of these aspects.

A theory that bring together the insights from these theories and other observations about motivation into a single, usable 'working model' ought to generate more accurate prediction and better control over behaviour.
A PRIMER
To understand behaviour we must focus on events immediately preceding it, and work backwards from there. So we start with RESPONSES which are generated by the balance between IMPULSES AND INHIBITIONS acting that the time. These can be triggered by what we often call instinct or habit, or generated by MOTIVES which are feelings of attraction or aversion to things that we can imagine (i.e. wants or needs). These can be generated by drive states and emotional responses, and by EVALUATIONS. These are beliefs about what is good or bad, useful or detrimental etc. and stem from inference, recollection, communication and motives, and by PLANS. These are more or less specific intentions regarding future actions. We are motivated to form them in anticipation of future circumstances or when current motives do not have sufficient priority to win through against others present at the moment.

Our disposition to react in particular ways with plans, evaluations, motives, impulses and inhibitions is shaped by experience through: HABITUATION and SENSITISATION, ASSOCIATIVE LEARNING and MEMORY. Our mental representations of ourselves as we think we are and as we want to be (IDENTITY) have a special place in generating evaluations and motives. SELF-CONTROL refers the effect of evaluations arising out of identity.
MOTIVATION

'... is what energises and directs our behaviour. Given all the things we could do in a given situation, it determines what we actually do.'