0.05 significance has a 1 in 20 chance of being randomly occurring (1 / 0.05 = 20) and a result of statistical noise rather than evidence of a pattern. This is

0.05 significance has a 1 in 20 chance of being randomly occurring (1 / 0.05 = 20) and a result of statistical noise rather than evidence of a pattern. This is why reproducibility is important in science - future trials and tests will fail to reproduce the exact pattern of events needed to produce the statistical noise and so the null hypothesis will be accepted instead.