Princeton did a study which states Facebook's growth can be compared to an infectious disease, something that spreads quickly and dies suddenly. The study predicts the amount of Facebook users will decline by 80 percent between 2015 and 2017.
In other words, users will lose interest as their peers lose interest, quickly, creating a snowball effect.
However, not everyone agrees with the study. "We think it's unlikely Facebook will see major disengagement over time," says Mark Mahaney, managing director and lead Internet analyst at RBC Capital Markets.
According to Mahaney, one should consider how the increased use of mobile devices will naturally boost overall Facebook user engagement and how a strategic purchase by Facebook of another social media site, such as Instagram, can significantly impact overall usage of Facebook.
(Read more: Are Facebook's revamped ads a Google killer?)
As a side note, Facebook has never reported any decline in daily active or monthly active users—only increased growth and engagement.
In response to an inquiry from CNBC, Facebook said it does not comment on studies and is in a quiet period.
—By CNBC's Christina Medici Scolaro.