Don't lose YOUR bitcoin too. Doing an annual recovery phrase check up can help prevent you from losing your bitcoin and ensure you're able to restore your wallet when you really need it. Pick a date and keep an annual reminder on your calendar.
GO FIND IT
Remember where you hid your recovery phrase and go find it. If you can't remember, better go looking. If you can't find it, move your funds to a new wallet with a new recovery phrase. Consider a more memorable hiding place.
CHECK IT'S STILL THERE
Get your recovery phrase. Is it there? If not, move your funds to a new wallet ASAP. You should be able to get your recovery phrase in a reasonable amount of time. If you can't, that's a problem. How do you expect your future self to get your recovery phrase in an emergency?
LOOK FOR DETERIORATION
For paper, look for tearing, holes, and overall structural feel. It shouldn't feel fragile. For metal, look for rust/corrosion. If you see any of these signs, consider better sealing containment, stronger material, a more environmetally stable location, or refreshing your recovery phrase's structural integrity by making a new copy.
CHECK FOR TAMPERING
Check for evidence of handling (fingerprints, markings, creases, etc),changes in surroundings (different placement, items moved/opened, etc), and the handwriting. If you suspect tampering, move your funds to a new wallet. Consider using a lock or a tamper-evident bag.
RECOVER YOUR WALLET
Go through the motions of recovering your wallet on a different device. Consider doing it with someone who will inherit your assets. This will be good practice for both of you. This is also a tamper check to confirm it does indeed recover YOUR wallet. Someone might have replaced your recovery phrase without your knowledge.