Does Falling In Love Really Take Time?

Some people fall in love after years of dating, some say it takes years of being with someone in order to know whether or not you love them. Others say they knew immediately or at least after a few days or weeks that they were in love. Can love truly be real after such a short amount of time? Do you have to be with someone several years before knowing they're "the one"? I personally think that even if you don't want to admit that you love a person after a short time, you know early on whether or not you can see yourself with that person and if it takes you years to know you truly love a person that may not be such a good sign. To each his own.