Think of peer review as a quality-control system. When a team of reviewers gives a green light to a particular paper, they are saying the science described in the paper is valid and trustworthy. This is similar to what quality-control inspectors do at a manufacturing plant. They check products by sight, sound, feel, smell or even taste to locate imperfections that might cause harm or dissatisfaction among end-users.
Inspectors adhere to strict quality standards, discarding any product that doesn’t meet the standard. Peer review does the same thing by setting a scientific standard.
Validating scientific results benefits everyone, from the scientists doing the work to professionals like you who eventually read about the research or hear news of it from colleagues and friends.