Beliefs are our perception of the universe and our place in it. It is our pair of glasses that we don to view events and things and determines what we pay attention to or ignore and they are totally subjective.
To put it another way it is our choice of beliefs that makes sense of our universe to us by explaining our experiences and what we see and know. If we choose to see the universe as a dark and hostile place; then, it is. We are always looking out for and protecting our self-interests.
This is a primary focus of a lot of self-help programs to putting you on track for your "quality" life that you deserve and can have with their program. Change your beliefs (perceptions); especially limiting ones, and you are on your way. Is it that simple?
We have two people who are offered a chance to accept a new job that will give them more opportunity, more money, and more things but it will mean almost no time for their family.
How did they make the choice? One person accepts and one person declines. Does the one declining have some limiting belief holding them back? Not necessarily.
One person defined the value of the new job as providing for the family in an economic sense and a necessary sacrifice in spending time with the family. The other declined by defining the value for the family as being involved and spending quality time with them.
Our beliefs affect how we see things but it is our values that choose for us.