In software engineering, a software should pass several tests in order to get certified. One of the tests is the exposure to Randomness (Monte Carlo method) ; The software is bombarded by random values as input (the values can be either useful or meaningless) and the results are checked. The longer the software is exposed to randomness without defecting, the more confident we become about its quality. The point is that randomness distributes the input vectors along the whole input spectrum in an equal manner so that any particular value get the same chance to get tested.
In life, it’s also important to get exposed to randomness from time to time: It’s really useful to search for new friends, talk to new people, try new things even those things we don’t like to do. The more we are exposed to randomness, the wider our perspective become and the more confident about ourselves we become.
Anyone can do the things he’s used to do, or he likes to do but this is not an indicator of robustness. If a software works correctly on some very specific input entries, it is not necessarily bug-free. Most vulnerabilities come from inputs where the software is not supposed to work on.