Peer review in its original intent is about validating that this particular paper is following scientific method. And that it is not completely made up or plagi

Peer review in its original intent is about validating that this particular paper is following scientific method. And that it is not completely made up or plagiarized. And most importantly is an honest try, not committing obvious mistakes and that the conclusion is supported by some evidence. People sometime confuse peer-reviewed with peer-checked which means in most cases reproduced independently. Of course in some fields things get complicated but the core idea of peer-reviewed is the same. You can consider it as an effort to maximize signal to noise ratio in science more than fact checking process