Furniture, Wood and Cabinetry Finishing - refinishing kitchen cabinets

My solid oak kitchen cabinets are showing there age (10 yrs). In certain spots, not all over, the finish has worn away, particularly in high use areas like drawer fronts under the sink. My intuition is to clean, lightly sand, then apply a polyurethane (three coats) only in the spots that need it. Will this work or do I have to do the full job? I'm not sure what the finish is on them now, likely a lacquer? or Shellac? Will the poly adhere? Will this look ugly? I don't want to end up divorced here....

If the cabinets were factory made (and finished) the finish is lacquer. Polyurethane will not adhere to a lacquer finish.

You can, however, clean the cabinets (Murphy's oil Soap works well), wipe them dry,leave them alone for 24 hours to make certain they're completely dry, then apply an aerosol lacquer.

I would try this on a single drawer (removed form the kitchen) before going whole hog. Spray the entire drawer front - not just the area that's worn. Several coats will probably be necessary.

Let it dry completely before evaluating your efforts. Let me know how it turns out.