The idea of keeping things simple is one that I feel is very important in the field of digital design. At the end of the day, the medium we work with most is technology, something that is super complex within itself. With so many options and routes available to find the outcome, over complexity along the way can just cloud the final result to the point of forgetting what your idea was in the first place.
With that said, just making something simple for the sake of simpleness wont always yield great results either. It might be a little extreme of an example but can you think back to when you were 2 and you just got that toy where you had to figure out how to fit the square, triangle, and circle blocks into their corresponding holes? It was fun for a minute then your mind wandered and you found yourself leaving the toy and eating some crayons. I can parallel this in a design sense because I want to create something that is simple enough to be dynamic and remembered, but not too simple to be easily forgotten. A great example of doing things right would be the nike logo.
"Everything should be made as simple as possible, but not simpler." - author unknown