More leads: visitors who see positive reviews are more likely to take an interest in your company.
More click-throughs: while they browse your site, the positive reviews they just saw will be in the back of their mind. Seeing other satisfied customers will make it more likely they will complete a sale.
More effective conversions: reviews decrease the likelihood of buyer’s remorse. They will know a good experience with your product was not a one-off and it can give value in the long run.