I am always surprised that no one in these threads seems to mention Pam or other equivalent cooking sprays. A million years ago, before these sprays existed, I worked in a little bakery where we brushed a homemade oil-and-lecithin mixture onto our tinned-steel loaf pans and it worked beautifully to eject the baked loaf spotlessly with a tap and a twist. The pans weren’t usually washed because the lecithin built up and became impressively non-stick. These sprays are basically the same thing.
I just counted that I have 9 cast iron pans and use the spray to maintain the seasoning on all of them. In regular use, they get a good spray to start, then oil added if I’m frying. After cooking, if I’ve had to scrub off something I’ve burned or if I’ve cooked liquid and the seasoning is dull not shiny, the pan gets another good spray and wiped down before storage. Otherwise just a rinse. With a new pan or an old pan that’s being rescued, you can get the seasoning started with the spray and some warm-ovening, for as many cycles as you want to build up the finish.
Overall this has been as low-maintenance and effective as I think you can get and keeps all my cast iron in frequent rotation. I had tried many of the oil techniques before and they never worked as well.