UPS is one of the highest-yielding dividend stocks on the S&P 500, and it has been increasing its payout in recent years.A dividend shouldn't be the main reason to invest in a stock. But when you're talking about a quality business that also has a solid dividend, especially a safe one, that could make it too good a buy to pass up.United Parcel Service (UPS +2.10%) is a leading company in the logistics industry, but in recent years it has fallen out of favor with investors, as fears are rising of a slowdown ...