Autographed baseballs are not only the most popular items in all of baseball autograph collecting -- far outpacing bats, caps, helmets, jerseys and photos -- but their popularity has spread to other sports and genres. Plenty of collectors desire baseballs autographed by actors, actresses, basketball and football players, politicians and just about anyone famous. I don't really understand the phenomenon myself, but it's reality.
Unfortunately, autographed baseballs come with a serious problem. They are prone to possible discoloration and fading over time, like the Cal Ripken autographed 2130/2131 commemorative baseball shown here. This is the case even if you use the right pen and immediately put it in a baseball cube without barely handling it.
The "right pen," by the way, is a blue ballpoint pen. Many if not most professional collectors like the Bic Cristal disposable pens, but on baseballs ANY blue ballpoint pen is better than ANY color Sharpie. A autographed MLB baseball signed in Sharpie is usually a ticking time bomb that will frequently start to bleed or fade in a matter of months. Of course, there are lucky owners of rare Sharpie signed baseballs that have lasted years with minimal bleeding or fading.
The situation with baseballs signed in blue ballpoint pen is not as dire. Many of them will look just fine years down the road. However, some will fade and bleed for no apparent reason. You could get a dozen MLB autographed baseballs from the same box signed on the same day, put them away, and check them years later and notice some look like they were signed yesterday while others are severely faded or discolored. In the olden days (mostly during the fountain pen era), collectors sometimes used shellac in a futile effort to protect the signatures. They ended up doing more harm than good.
The reason, of course, for the seemingly random discoloration and fading of baseballs is the leather. As an organic material, it ages inconsistently and unpredictably. So if you are the victim of having your favorite autographed baseball look nothing like when you originally got it, blame the cow!