Typically, well written answers have a tendency to get rated more often than something that wasn't well thought out, or was just thrown together with bad spelling, no capitalization and lousy grammar. If you aren't putting much effort into your answers, then changing that may help you be rated more often.
Other than that, sometimes people are just plain selfish. They don't think about other people and just exist to take from others. They don't rate because they can't be bothered, which is sad. [ DangerNerd's advice column | Ask DangerNerd A Question ]
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