A Publons Score gives a quick insight into how the experts (the Publons community of expert reviewers) rate a manuscript. It is not intended to replace peer review but is an evaluation of the final submission or published paper. Each Publons account may score a paper only once. 

Scoring is always completely anonymous and scores are not displayed until the manuscript has been published.

Scores help with comparing and filtering published articles giving a more meaningful indicator of an article's quality than indirect metrics, such as a Journal's Impact Factor.