Abdication of Leadership Responsibility
Both of these terms reflect an abdication of leadership responsibility, almost always on the part of formal leaders.
Followers expect leaders to use their formal power and authority to set direction for an organization, and help the organization get to the destinations. That requires being "in front" and making decisions.
Some leaders, seduced by the idea that the leadership role involves "serving" those that are lead, lose sight of the decision-making and direction-setting aspects of leadership, and try to steer the organization by reading where the followers want to go, rather than setting direction based on the needs of the entire organization in its context. While serving followers is not a bad idea at all, when a leader is unable to supply direction and guidance independent of followers, the ship founders.
Leadership by polls is often the expression used to describe political leaders who are more interested in getting elected by appearing to please the populace, placing popularity in a more important position than integrity, creating vision, goals, etc. They appear to stand "for nothing". It's a dubious tactic, even in politics.
Leading from the rear is a perjorative term that applies to leaders who lack the strength to be ahead of followers. Its origins probably lie with the military, where the leader sits behind the lines and makes decisions without being in the midst of the battle. Leading from the rear often results in the leader being out of touch with the realities of the context, and out of touch with the needs of the situations and followers.
What is "leading from the rear" and "leading by polls"?