The above quotation comes from Shakespeare's great tragedy: "Julius Caesar", of which, most scholars interpret this as meaning that the evil that men have done are more often remembered, than their good deeds, which, often seems to be true. The reason that this is true, though, has a lot to do with mankind, in general, of which, mankind often has difficulty in controlling their own weak passions of jealously and envy, so that, they take a certain perverse pleasure in seeing people that are held in high esteem, knocked down a few notches, so that therefore this makes them feel a little bit better about themselves, in comparison to them, and this is exactly why gossip is so prevalent in society, for the same basic reasons.
There is, however, another perspective that is important to take account of, in regards to the departed having left this world and their evil living on, and that is the fact that there are certain deeds and actions done, which can have consequences that go far beyond the present, so as to thereby reach into the future. That is to say, if you cheat, lie, and steal from people, yet, you seemingly have not suffered any punishment for having done so, the perception by others, may be to overlook these flaws as even being flaws, because of the other good qualities that you have. So that, having seen that you have cheated and stolen from others, they will have a tendency to copy those things, for self-serving reasons, in their belief, that since it apparently worked for you, then it will apparently work for them.
Every time that a public or a private figure that is of importance to you, does something that clearly is wrong, the perception of how you look upon that wrong, will make a material difference, as to whether or not it will be potentially perpetuated by yourself. In other words, all of us make mistakes, but those that are in influential positions, have an incumbent responsibility to own up to their mistakes and when they are dismissive of them, or excuse them, or ignore them, it is not any wonder, that other people will emulate those same sorts of mistakes, because they figure that if it's okay for them to do this, therefore it must follow, it's okay for us, to do the same sort of thing.
In point of fact, the lives we lead are complicated, and if we are unable to fully see the whole of another, though our prism of who and what they really are, and of what they aspire to be, than our interpretation of them may easily be flawed. This type of distorted vision, when combined with the lack of proper discernment, allows far too many people, to dismiss the good and righteousness qualities that a given person has, and instead, to pick up or to emphasize their evil habits and bad dispositions, under the guise, that all of this must be okay, because it apparently worked for them, so that the evil lives on in us, for our failure to comprehend that evil can only live on, if we allow it to live and to fester inside of us.