Maslow's Heirarchy of Needs refers to the theoretical fundamental structure of human individuals in regards to what they need to do first in order to have a successful life.
1) Physiological Needs is at the bottom because it is the most important: if you don't have the basics or the necessities to take care of yourself, the rest will collapse.
2) Safety refers to maintaining your health and finances; if you're in a bad state of mind and physical condition, you can't really enjoy the social aspects of life.
3) Love/Belonging refers to connections with family, friends, and love partners. If you lack this emotional connection, there is a high chance your self-esteem won't be high. However, if the people around you are also in bad condition, you're probably better off without them and so because of that, you will have a higher self-esteem since you know you're better than the people around you.
4) Esteem: your feelings about yourself will be determined by the conditions below this stage. This self-esteem will then determine how far in life you want to go.
5) Self-Actualization is the peak of your human condition. If everything else below this stage is great, then you will achieve great heights and will be the best you possible through your acquired determination. If everything below this is bad, then your desire to become the best will not be enough to actually take you to greatness because your low self-esteem will make you not believe in yourself. You have to believe in yourself if you wanna get somewhere.
