The best movies tend to be the ones you buy into. Whether it is because you relate to the characters, or the plot, or because they are realistic. If you buy in you are captivated. If you don't your mind wanders.

Our lives are the same. Sometimes we are bought into what's happening around us and are engaged. Other times we are not and are distracted.

Buy in all depends on our perception, so control it. If you want to be engaged and feel something strongly choose to buy in. If a situation is painful and you need a break choose not to.