You really haven’t been paying attention, YoursTrue.
Scientific theories are former falsifiable hypotheses that have been VERIFIED through TESTS & OBSERVATIONS, YoursTrue.
TESTS & OBSERVATIONS means “evidence”, “experiments” & “data”.
It is evidence that will either refute the hypothesis or verify the hypothesis. That’s how you would “scientifically” test any hypothesis.
Evidence can also lead to updating existing theories, which can be any of the following:
- corrections to any errors of the theory
- amendments or modifications to theory, especially when there are better or improved explanations
- adding new portions to the theories when there are new information from the evidence; this can lead to expanding the theory.
- or removing portions from the theory that have been refuted
Astronomy and astrophysics are some of the sciences that are constantly updated, because new discoveries provide new information or data about for instances, planets, stars, supernovas, blackholes, galaxies, etc. These discoveries and data often come to us because of our technology have advanced, that provide better observations or more accurate measurements.
For examples, before space observatories, all observations are made from terrestrial telescopes, which are hampered by the Earth’s atmosphere, pollution and climate. Then in 1990, the Hubble Space Telescope (HST) was launch that provide clearer images than ever before, about the Solar System, then other stars, star clusters, nebulae within the Milky Way, other galaxies, and the universe. Then even more recently, the James Webb Space Telescope (JWST) provide even more higher resolution in the visible light spectrum and near infrared than the Hubble. There are many more other telescopes (past & present) that used other parts of EM spectrum for observations, such as ultraviolet, x-ray, gamma ray, etc.
The points in all these advancements in these technologies and new discoveries plus new data, is to improve our understanding about the universe. These new evidence & data can update the existing knowledge, and if necessary, debunk existing theories.
Medicine is another area where science are continually advancing, including in the areas of treatments, diagnosis, testing, etc.
Theories can be changed, corrected, updated, and when necessary, remove because when there are either better alternative (hence replacement) or when refuted.