Reproducibility is one of the foundations of science. If something is true, it should be true every time. While it’s exciting to create new studies with new results, it is equally important to recreate studies done by others.
It may come as a surprise to many that science never proves something to be true. We can falsify a hypothesis, but there is always a chance that our positive results are due to chance. Reproducing studies is one way to reduce that possibility.