That was something my grandfather taught me. He repeated it many times as a reminder to himself, I think, but I absorbed it. Over the years it has become clear that it means what it says. That is, being pleasant might not make others love you, but they won't have cause to hate you because you are civil and pleasant. It is true that some very pleasant people come to a bad end. I would wager that it is rarely a result of being pleasant.
In the world I now inhabit - let me remind you, I am an older woman with a long history of behaving and looking very male - I don't try to fool people. I dress and act as a woman of my age would because that is who I am. It is pretty hard to imagine though that, with hair that betrays male-pattern baldness and the height and shoulder width that a lifetime of testosterone gave me, there aren't many who guess that I am trans. So what is a gal to do?
Remembering my years of training, I am pleasant with anyone who allows me to be that way. Because I live in a small town people generally talk to one another. It isn't like being in Toronto where commenting that the weather is beautiful to a stranger gets you dirty looks. In consequence, although people might know very well that I am trans, people also know that I am friendly. They aren't afraid of me. Sometimes they say things like "what a lovely outfit that is ... you are always so beautifully dressed". I don't think they say that to other women who come in the store, but I am always pleasant to them, so they reciprocate in their own way. I appreciate it.
What might come of this is that people who didn't know much about trans-folk might have learned that transpeople are not scary. In high hopes, some young people who are afraid they are like me (because being different is the worst thing that can happen when you are young in our society) might realize that coming out and living your own truth isn't a bad thing.
I am currently in my early years as a senior citizen. Someday, if I am lucky, I will get old. I might be unable to care for myself. Some of the young folk in this community might be caring instead. I hope to be able to stay pleasant for them. I might even be able to continue to educate the muggles.