Maslow created a well-known theory of human motivation. It is a hierarchy established by the theory of human needs Maslow believes are universal. These needs include, from bottom to top, physiological, safety, love/belonging, esteem, and self-actualization. Let’s explain these needs before moving onto what motivates consumers.

Physiological Needs- These are known as basic necessities needed to live—food, air, water, shelter, reproduction, etc.
Safety- Safety involves the need for being stable and feeling safe.
Love/belonging- These are your social needs. Spending time with friends and family, socializing. A feeling of being wanted and needed either as a friend, parent, lover, etc.
Esteem- This is personal self-esteem. How you feel about yourself and how you perceive your status.
Self-actualization- This is the need to try to be the best at what they do and improve themselves professionally and personally.
To understand what motivates a consumer to purchase a product or stay loyal to a brand, marketers need to understand what the needs and wants of consumers are. The theory of need hierarchy helps marketers understand and see what motivates consumers in terms of fulfilling their basic needs. Needs and fulfillment are the basis of motivation.
What motivates customers to buy is the need for the product. Essentials items such as water, food, and toiletries are necessary, but then it moves to why does the consumer purchase the brand of water or toothpaste? Is it what the brand stands for? Is it what it offers in terms of its competitors? This is where the marketer needs to get clever to win the purchase of the consumer.
Once the consumer realizes they need the product, their next motivation is if the product will make their life easier. We live in a time when there are time constraints, and convenience is of the utmost importance. What does your product have over the competition that will make their life easier? Is there a specific feature that is valued more than the competitors?
Once these factors have been addressed, it then comes to the consideration of exclusiveness and status. It is about choosing Pepsi over Coca Cola or choosing iPhone over Samsung. This product is not a necessity, but it is fulfilling a desire and which brand fills that desire moreover the other. Both products are similar to each other, but why do consumers choose one brand over the other? This is what great marketing accomplishes. When you give a consumer a reason to choose your brand over the competition, then you have succeeded in reaching that consumer. Below is an article that goes into detail about consumer behavior and motivation.

http://consumerbehaviour4vtu.blogspot.com/2009/03/motivation.html