"Once the herd starts moving in one direction, it's very hard to turn it, even slightly"

This quote by Dan Rather talks to the power of groupthink and the trouble of going against the grain. It suggests that when a large group of people are all relocating the exact same direction, it can be very hard to sway them from their course. This is since the group is most likely to be combined in their beliefs and opinions, and any effort to change their minds may be met resistance. It also indicates that it is simpler to affect a group when it is still in the early stages of forming an opinion, rather than when it has actually already comprised its mind. This quote works as a suggestion that it is important to think for oneself and to be available to different perspectives, rather than blindly following the crowd.