Bethany Heck gives a long, in-depth explanation of why it can be acceptable to go against the widely held opinion of “do not use too many fonts” in a design. She starts by recognizing there is a reason this specific guideline came to be:
We can all point to questionable designs that use an excessive number of typefaces. You can sense when a designer is trying to compensate for a deficiency by throwing more typefaces into a piece.
But she goes on to give good advice for this “rule” (which can be applied to any other guideline as well):
… don’t let one designer’s opinion affect how you approach solving a problem. Given the right content and the right faces, any number of typefaces can work in a design.
From there she goes on to give lovely, nuanced examples. It’s a long read, but a beautiful one that is worth the time. This is the best the web has to offer: someone with talent and experience takes the time to share their knowledge with painstakingly crafted examples that illustrate their point.
Be sure to check out Bethany’s project of love, The Ephesus League. What an example of a master at their craft.