what first comes to your mind when you hear the word obvious?
That too many people misuse the word all too often, (apply it when things aren't as obvious as they perceive them to be). While it may be "obvious" that people's perceptions can and do differ, some will continue to insist that their own perception ought to be shared by others, (unless something is bluntly obvious - like "the rabbit died" and, "there may be non-obvious implications").