Luggage locker

The lockers are fine if they are available. Price can vary a lot but a couple euro an hour is not out of the question. Left luggage is often cheaper.

We often will drop by our hotel even if the room's unavailable and drop off our luggage prior to our checking in.

Seldom use luggage lockers.

Recently, they have installed credit card enabled lockers and they cost more. The initial rental is only 6 hours, and you have to pay a certain rate per hour thereafter. Scan the QR code on your ticket and they will display the added amount you have to pay to open the locker. At least my experience at Luzern station. Needs tap enabled credit cards.

Example at Zurich HB. Click on "Equipment and lockers"
https://www.sbb.ch/en/travel-information/stations/find-station/shopville-zuerich-main-station.html