Why pull hair back to one side?
When choosing to have your hair down for your bridal look or for other events, it's important to consider how it is going to be placed over your shoulders. This depends on the look you are going for but other factors come into play.
We normally tend to play with our hair throughout the day, pulling some hair either both sides to the front, one side to the front, or all the hair back. Try to notice which is what you tend to do the most and try to choose a hairstyle that matches that tendency, this way it will be easier for you to keep it in place.
Regarding a bridal look, think about how many people will want to hug you and kiss you. Having the hair pulled back from one side will give you a free side to hug people without ruining your hairstyle and keeping it flawless for the longest time.