The current understanding of motivation is based on a number of proposed theories researched within the field of psychology. It is important to note that the root of motivation stems from our emotional wellbeing, but can include our biology, social climate or cognitive resources.
William James (1842-1910) best known as a philosopher first proposed Instinct Theory that included a list of human instincts described as attachment, play, shame, anger, fear, shyness, modesty, and love that all play a part in motivation inclination. Within this time period, psychologist John B. Watson (1878-1958) takes centre stage with his knowledge gained through research on human behaviour. Watson informs us of a change of climate in the field of psychology with his statement:
"There are for us...no instincts. We no longer need the term in psychology. Everything we have been in the habit of calling an "instinct" today is the result largely of training-belonging to man's learned behaviour."
Although the competitive atmosphere in the field of Psychology should not cancel out efforts of previous research, James built his perceptions on the Theory of Natural Selection, by Charles Darwin (1809-1882). The Theory of Natural Selection suggests that the features of an organism that help it survive, and reproduce are more likely than other features to be passed on to subsequent generations.
This can be dissected by painting a sad picture of social equality, where one side of the spectrum exists a dysfunctional family wherein a child grows up with neglect, and lack of support, versus growing up in a family of academic achievers. One child learns it is not safe to have wants, or needs develops low self-esteem, fragments from social trauma, and develops depressive tendencies along with addictive personality, and poverty consciousness, while the other child's potential is protected. This protected child learns how to set goals, possess a positive self-esteem, find meaning in purpose, and establish economic stability. He then raises a large family, which results in the survival of his gene pool for generations to come.
Specifically, what aspect of human nature contributes to the survival of one's species, or gene pool? Research reveals the power lies in the hands of the nurturer in the first seven years of life when the mind is programmable. This does not deny that society plays a part in creating a means for anyone to develop potential regardless of oppressive circumstances, however, parenting is influential in establishing motivational behavioural patterns. The way parents influence motivation is through the promotion of healthy interdependence. There's an old saying, usually attributed to Confucius, that goes something like "Give a man a fish, and you'll feed him for a day. Teach a man to fish, and you've fed him for a lifetime."
Healthy interdependence means teaching our children to be independent on their own through building self-esteem by establishing skill sets at each developmental stage as appropriate. This process is the goal of parenthood, and the vehicle through which love is expressed. Abandonment on the other hand may be responsible for an inadequate reward system, and low self-esteem within an energy field of discouragement. Encompassed in this discouragement field exists hopelessness, and apathy. Feelings of hopelessness produce skepticism that leads to inactivity, and impairs motivation.
An apathetic personality resorts to face saving excuses for inaction. Belief motivates the inaction promoting the inability, or refusal to take responsibility. Survival for some means abandoning the need for independence, this is where we get extreme cases of individuals stuck in homelessness, and addiction. An apathetic state involves repressed anger, when one attempts to embrace core needs through the process of goal achievement, shame and guilt may be triggered.
An apathetic lifestyle disregards the value of life, and divinity as Source. A healthy parent will provide recognition for effort, along with guidance toward attainable goals that build esteem, a discouraging parent leaves their children seeing no point in trying to make an attempt at a higher level of functioning. Human behaviours can be instinctually driven, or motivated by positive, idealized goals.
A sure way to quell lack of motivation when apathy, despair, and hopelessness exists is to do some self-reflection into your life, thinking about a time where you may have developed an internal belief that may be described as, "I can't". Recognize the experience of discouragement, and if you felt that there was no way to win. Remember how you gave up on yourself, and everyone in your life whose responsibility it was to meet your needs. Remember how this turned you away from your spirit. Sit with that for a moment.
The bottom line is this, the requirements for the survival of the species does not change, as everyone needs food, light, and water to survive. An individual can enhance the survival of their gene pool through reproduction regardless of economic security, this is a choice. Fundamentally, we need motivation to change any circumstance that points us in the direction of success. Motivation requires self-love, healthy relationships, support systems, and a personal belief that honours one's inherent right to success that further promotes the will to take action. Seek Bindu - the point of creation, and all else will be added unto you.

Experts in the field of Motivation
References:
Swan, Teal - How to Cure Apathy: YouTube
Hawkins, David R. M.D. Ph.D. - Transcending Levels of Consciousness, The Stairway to Enlightenment