Refinishing is a finish change, not a structural one. It transforms how a kitchen looks and leaves the layout, the boxes and the storage exactly as they are. That is the right trade when the cabinets are fundamentally sound and simply dated or worn.
Check the boxes before deciding. Solid wood or good plywood carcasses with working doors and drawers are worth refinishing. Particleboard that has swollen at the sink base, delaminating shelves, or doors that no longer sit square are telling you the cabinets are at the end of their life, and a beautiful finish on a failing box is money spent twice.
Layout is the other honest test. If the real problem is that the kitchen is laid out badly, or you need more storage, refinishing will not solve it and you will still be unhappy afterwards.
What refinishing actually involves: doors and drawer fronts come off and are labeled, hardware is removed, and everything is degreased, because kitchen cabinets carry years of cooking residue that will reject paint if it is skipped. It is then sanded, primed and sprayed. Spraying instead of brushing is what produces the smooth, factory-like surface instead of brush marks.
Expect the kitchen to be partly unusable for several days, and expect a good contractor to tell you honestly if your cabinets are not worth doing. That answer is worth more than the job.