There are many illuminating ways to understand politics, but one is as the practice of attempting to shape and direct the collective life of one’s community. Those who do politics typically seek to influence the collective life of the community with what they regard as morally good objectives in mind. Hence, at least according to this understanding of politics, outcomes matter enormously.
This goes part of the way to explaining why consequentialism is an approach to morality that has such purchase in politics. Simplifying a bit, consequentialism is the view that the moral rightness of an act depends only on its consequences.
Perhaps the most well-known objection to consequentialism is that it seems to permit acts which most people believe are obviously morally wrong. Familiar examples of such acts include lying, breaking promises, failing to show gratitude or loyalty, and imposing harm on others. This implication is typically illustrated via highly unrealistic thought experiments, but let me use three quite different recent examples from British politics instead.