It isn't but it kind of is. It is a 95% chance that you should reject the null hypothesis. For example if we flip a coin a 5 times and get heads every time that gives you a p value .03 for rejecting the null hypothesis that the coin is fair. If I run the five coin flip experiment a 100 times and never once reproduce a significant result is it because gee science is hard, or is it because you hit one of those 3% of cases. The same goes for real science if you can't reproduce it more often than not then you might be close but you haven't figured it out yet.