There are few things as rewarding for an investor as stumbling upon a great dividend stock like telecommunications giant AT&T (T -1.22%). Not only do stocks like this generate healthy quarterly income, but they also typically come with lower volatility. 

But what exactly makes a dividend stock like AT&T such a great addition to an income investor's portfolio? As Motley Fool contributor John Maxfield discusses in the following video, there are at least three reasons.

First, it's paid uninterrupted dividends for 30 consecutive years, making it one of the most reliable income-generating stocks in the market today. Second, AT&T's quarterly payout has increased consistently over the past three decades. And finally, its payout ratio is only 53%, which is a comfortable percentage that leaves room for both organic share price appreciation and future dividend growth.

Want to learn more? Check out the following video, in which John delves deeper into the reasons dividend investors love AT&T.