This is my rather informal answer, so take it with a grain of salt: Theories are rejected/ignored when they do not have a good backing or implications that they might be correct, and are conclusively rejected when experimental data disagrees with them. Theories are considered when they seem plausible, and if all experimental data agrees with them, they are accepted.
there might not be enough proof
Some one proves it wrong.
A scientific theory may be changed when new empirical evidence contradicts the existing framework, demonstrating that it cannot adequately explain observed phenomena. Advances in technology or methodology can also lead to new insights that challenge established theories. Additionally, if a theory fails to make accurate predictions or does not integrate well with other established scientific knowledge, it may be revised or replaced. Ultimately, the scientific process is dynamic, allowing for theories to evolve as our understanding of the natural world deepens.
Because technology might change in the future.
A "law" contains absolute certainty or scientific truth. A theory is very close to being a law, but without the absoluteness. That is what a theory is. If you have a pretty good idea of how something in science might work you might form a hypothesis (hye-POTH-uh-suss). With enough additional proofs and evidence, a hypothesis may someday turn into a theory.
there might not be enough proof
its to old
It is to old
Some one proves it wrong.
A scientific theory may be changed when new empirical evidence contradicts the existing framework, demonstrating that it cannot adequately explain observed phenomena. Advances in technology or methodology can also lead to new insights that challenge established theories. Additionally, if a theory fails to make accurate predictions or does not integrate well with other established scientific knowledge, it may be revised or replaced. Ultimately, the scientific process is dynamic, allowing for theories to evolve as our understanding of the natural world deepens.
Because technology might change in the future.
Continuing research can turn up new or conflicting information regarding a theory or scientific law. It will then be changed even after general acceptance.
A "law" contains absolute certainty or scientific truth. A theory is very close to being a law, but without the absoluteness. That is what a theory is. If you have a pretty good idea of how something in science might work you might form a hypothesis (hye-POTH-uh-suss). With enough additional proofs and evidence, a hypothesis may someday turn into a theory.
If a new theory better fits the data overall or simply because new and significant data disagrees or the method which brought about the original theory is invalid.
There was once a theory, that electromagnetic waves might be used for communication over long distance. Your mobile phone is the proof that the theory was correct.
Scientific information constantly changes as new information is discovered or as previous hypotheses are retested. New information can lead to changes in scientific theories. When new facts are revealed, a current scientific theory might be revised to include the new facts, or it might be disproved and rejected.
A scientist might reject a scientific theory if new empirical evidence contradicts its predictions or underlying principles. For instance, if experimental results consistently show outcomes that the theory cannot explain or predict accurately, this would undermine its validity. Additionally, if a theory fails to account for a significant body of existing data or if a more comprehensive alternative theory emerges, a scientist may deem it necessary to reject the original theory.