Some days you need to just put aside time to do maintenance.
On your tools. On your supplies. On yourself.
As a guy who runs multiple websites, I need to set aside time once per month or so to do routine upgrades on the software, clean up log files, and make sure all these systems are running soundly and securely.
The same habits apply to my art supplies. Once in a while I need to tidy up, clean my brushes and plates, test the collection of pens, and get rid of the various wrappers, tissues, and bits of trash that have accumulated around and in my kits.
It’s not a day that lacks productivity. It’s a different kind of productivity that is necessary to stay productive.