People say that Meta Descriptions have no effect on ranking. They are right and wrong at the same time. Meta description has no direct effect on ranking but has a huge indirect effect on ranking. Now take this case: Your site is ranking at #5, then according to Google’s algorithm your site should be getting a CTR (Click through rate) of 10% but because of your better Meta description you are getting a better CTR (may be 2 x 10%= 20%) then Google will get a signal that your site is liked by others. Google should promote your site up.