The implications of an idea are often used to judge its value. Theories or doctrines which imply a desirable or undesirable consequence are often judged "true" or "false" on that basis.
Some philosophers and scientists believe that the truth of an idea is unrelated to human evalutions of the worthiness of the idea's consequence. Politicians, on the other hand, typically assume that ideas with bad consequences are false - or at least they argue that way in public.
Some well-known examples include the theory of evolution, which is valuable for atheists and materialists looking for an excuse not to believe in God or an afterlife. If human beings did not evolve naturally but required an intelligent designer to produce them, then it's hard to justify one's lack of faith or refusal to adopt and practice a religion. Hence, the value of evolution: it provides a tidy intellectual justification for refusing to accept a Creator.