Choosing a perfect color for a room does not seem to be a big deal. Go to the store, choose a color that you like, paint your room and that is it. But, there always could be the “but”. Color shade is not necessarily same in your room as it was in the store. Different lighting produces different color shade. Same color does not look the same on different walls (across the window and next to the window).
To avoid disappointment and double cost, use sample papers, tape them to the different walls in your room and look at them in the morning, afternoon and night light. This way you see how you feel about that color before painting whole room.