I'll be uploading some posts over the next week, about how what you're learning / have learnt on this course can be useful for not just computer animated films, but even stop-motion films such as Laika's Paranorman, Boxtrolls and Aardman's "The Pirates! In an adventure with Scientists" to name a few.
To start off, I'll show examples of why the character design process you're learning is so important.
When you come to make your own films, more often than not there will be characters involved. These characters need to be worked into over and over again to know them inside out, to know what they will need to do, what their facial expressions or body emotions will look like, to make sure that they fit the story and style you're aiming for, and that they'll be able to perform how you need them to. This goes for characters in CG not just stop motion. If the character has a flaw in the design because you need it to do something after you've spent weeks making the thing but you didn't factor that in beforehand, you'll either have to hope Alan knows the answer, or you'll be starting again, and there's not usually enough time to start again. So to make sure you reduce the chance of not being able to move the characters head side to side because there's a massive chin in the way that would hit the character's large shoulder (just an example off the top of my head), it's important you think ahead at the character's design stage.
When you have a collection of designs, they also look really great laid out in a book or on posters for you to admire and show off to potential employers :)