They're always so vague it's impossible to actually learn anything from them. Anybody can benefit from, "Watch your step on this day," because you have a chance of tripping and breaking your neck and dying every day. If mine one day said, "You will engage in a battle with Chuck Norris" and gave details on how to win, and I did, then I'd believe in them.
As for "people born this month are kind, giving and selfless etc." explain pairs of twins where one is kind, giving and selfless etc. while the other is a conniving murderer.