If the T-bill rate drops, you get less interest. Treasury bonds, however, are an exception — you can buy those directly from the U. The problem with this system is that, because bond transactions don’t occur in a centralized location, investors have a harder time knowing whether they’re getting a fair price. As we said before, bonds are generally considered a less risky investment than stocks. If an issuer defaults on its obligations, you risk losing out on interest payments, getting your principal repaid, or both.