I've only bought the pan a week ago and used it three times. Hot dogs, eggs, and steak.
When I'm done I clean it with a scrubby sponge and once with a little bit of detergent, then put it on the stove to dry quickly. Then while it's hot I smear maybe a teaspoon of vegetable oil on it with a paper towel "brush".
In between uses it's wet with oil, as you can see in the picture. How much residual oil should there be? I had the impression that it would be dryer.
Also, how much should I scrub? I am not going to leave crust of beef on there, but I also don't think it's supposed to be scrubbed back to new smoothness.
Oh right. Every now and then (maybe every year or two if I've been using it a lot or if it starts getting a little gnarly) I'll use a tiny bit of soap when I clean it then I'll re-oil it, usually with olive oil. Maybe not best practice but it's been working fine for me.
Thank you!