Some older ones just need a light seal replacement.

After ruining more manicures than I can count, I totally get what @waderamirez is saying. I used to rely on just a top coat and would smudge my nails trying to check my phone too soon. One time, I left perfect fingerprints on every key while typing at work. Now with fast-dry drops, I can put on my shoes right after and not wreck the polish. It's like magic for impatient people like me who can't sit still.

But doesn't that just catch the error instead of fixing the cause?

Dealing with a flickering dash light last month. The code reader showed nothing, clean as a whistle. Spotted a frayed wire behind the glove box after poking around. Turns out it was rubbing against a bracket. Scanner probably thought it was a ghost in the machine. Fixed it with some tape and a zip tie, good as new.

Honestly, I usually look up and give a quick, "Everything alright over here?" Works most times without making it weird.