It is taken for granted that polls forecast the results of upcoming elections and that both incumbents and challengers disregard them at their peril. Many a politician lets poll results influence his position on the issues. Polls have evolved to the point that they help define government policy, that they determine government policy. The polling industry has no constituency outside the pollsters themselves and their clients. Polls are less a means of measuring public opinion than of manipulating it.
Polls distort the political process and turn it into a circus.
The beneficiaries of polling are the pollsters and the politicians who hire them. Everyone else loses. If the identical poll were conducted with a similar population, then the results would correlate within the margin of error. This is an assertion of consistency, or repeatability, rather than of intrinsic accuracy. The validity of the polling process depends upon a representative sample.