Some human being are so difficult to please, You can even go the extramile but they will still be unsatisfied.

It's how they were made

i simply put human beings are dynamic in nature..

Not even a simple thing can please them

LuckyAgbaze:
Not even a simple thing can please them

Only go out of your way to please people you genuinely care for, this way you're not bothered by how they respond as long as your desire to please them is fulfilled.
Although appreciation can be a good motivator to doing more, you shouldn't count on it from everyone...some people just don't know how to express their appreciation even when they feel that way.

For random people, just be yourself - not everyone will like or appreciate you either way.