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.
I commit all kinds of cast iron crimes, but honestly, just re-seasoning pans is fine. Oil and wipe with a paper towel. Cast iron can absolutely take a cleaning.
I fully clean mine with soap because I make spicy tacos at night in it, then flapjacks the next day. Nobody wants spicy flapjacks.
The real key is unscented/unflavored soap. then, reseason with just enough oil to keep it shiny. If you make it your main pan, it will get nice and seasoned from years of use. :)
Thank you very much!