Finally, statistical tests will confirm whether the predictions are correct or not. This method is usually so rigorous that it is rare for a hypothesis to be completely proved, but some of the initial predictions may be correct and will lead to new areas of research and refinements of the hypothesis.
In addition, there may be another unknown reason that explains the results. Most theories, however solid the proof, develop and evolve over time, changing and adapting as new research refines the known data.
Proving a hypothesis is never completely accurate but, after a process of debate and retesting of the results, may become a scientific assumption. Science is built upon these 'paradigms' and even commonly accepted views may prove to be inaccurate upon further exploration.
A false hypothesis does not necessarily mean that the area of research is now closed or incorrect. The experiment may not have been accurate enough, or there may have been some other contributing error.
This is why the hypothetico-deductive method relies on initial predictions; very few hypotheses, if the research is thorough, are completely wrong as they generate new directions for future research.