It's like the notebook becomes a museum piece instead of a tool... you're curating an exhibit of a life you're not actually living. That pressure to keep it perfect kills the whole point of writing things down. My ugliest notebooks with spilled ink and bad handwriting are the only ones I ever filled up completely. The mess is proof it was actually used for something real.
Honestly, I go the other way. My notebook is a tool, not a showpiece. I want coffee rings on the pages and scribbled-out to-do lists. That wear proves it's working. If it stays pretty, it's just a decoration that failed its job.